In Keltham's mind, a hypothesis is taking shape, a mental model.
To a Chelish eavesdropper, it would look like rather a lot of ~~~~. Seeing the idea as a dath ilani sees it, compactly and at a glance, requires a grasp of underlying math. If Keltham wanted to say it to Carissa, he would need to spell out rather a lot of things and also use a whiteboard.
Keltham's thought revolves around a standard dath ilani concept that Taldane has no word for. 'Intelligence' translated into this word in Baseline; but Keltham is starting to suspect that this reflects a mistake that Carissa and other language donors are making, not a translation accurate in the world. For translation purposes, one must then fix a new term.
Call this one 'thinkoomph'.
'Thinkoomph' is optimization-as-done-by-humans. Its figure-of-merit is correct prediction, choice of action leading to desired outcomes, the power of inner thoughts over the outer world, the power of cognition to apprehend and effectuate reality. Of course, humans do this in a weird idiosyncratic way, and a random possible simple optimizer that was about as powerful as an average dath ilani would not understand and manipulate reality in the same way as an average dath ilani. But if everyone involved is a human, then to speak of 'thinkoomph' as a thing-humans-do whose figure-of-merit is optimization, is not too unsensible a concept.
Keltham does not need to think about this part right now, he has already chunked the notion of 'thinkoomph' long ago. 'Thinkoomph' is a view into the processes that humans do to produce optimization, viewed from the standpoint where its purpose is optimization, and where the information-theoretic goal of the viewpoint you're taking is to make it easy to describe those usual variations among humans that contribute to the variations in their optimization power.
Thinkoomph then is not a single number but a structure with some internals. But it happens to be empirically the case that a lot of usefully-discussable smartness-components map not-too-terribly onto a unidimensional line, such that, holding the rest of a mind constant, you get more optimization power as you move up along the line.
For ease of visualization, then, consider thinkoomph as a seven-dimensional thing, because it happens that there's a useful component analysis like that in dath ilan which gives you seven dimensions.
Or consider thinkoomph as a machine with seven gears each of varying size, if you don't want to visualize seven-dimensional objects for some weird reason.
Suppose Detect Intelligence gives you an imperfect partial view of thinkoomph that's made up of, say, (1) speed/clarity of information retrieval plus (2) how much information you can maintain in short-term memory. Detect Wisdom gives you an imperfect partial view of (3) the piece of thinkoomph that's perceptual clarity, which critically has a subpiece (3a) that is clarity and detail and accuracy of introspection. Which is to say - shifting viewpoints from the machinery to the result that machinery produces - that Detect Wisdom imperfectly measures the machinery that grinds to produce reflection.
In dath ilan the proverb-poem goes: 'Beware lest what you can measure easily becomes all that you measure; beware lest it become all that you optimize; beware lest it become all that you ever think of.'
The people of Golarion know how to Detect Intelligence and Detect Wisdom, and that's it. So they think there are two components of thinkoomph. They invent two spells to boost the thing-that-Detect-Intelligence-detects and the thing-that-Detect-Wisdom-detects.
They invent headbands to boost the thing-that-Detect-Intelligence-detects. The amount the headband sells for depends on how large of a shift it produces in that handy spell Detect Intelligence, which, as everyone in Golarion knows, detects Intelligence. If the Detect Intelligence spell says that a headband produces a +3 to Intelligence, it's worth less money than if Detect Intelligence says that the headband produces +4 to intelligence.
Imagine now that nobody has invented Detect Wisdom yet, just Detect Intelligence. Imagine that somebody with a vision of broader thinkoomph builds a new headband that would, if you could also run Detect Wisdom, show to produce a +3 to Intelligence and a +3 to Wisdom. This headband is probably more expensive to build than the one that produces +4 to Intelligence, probably by a lot, and the Detect Intelligence spell says that it produces an inferior result than the +4 headband. So nobody builds a headband like that, if they don't have Detect Wisdom.
Does either Intelligence or Wisdom incorporate creativity, outside-the-box solutions, outside-the-box hypotheses? Maybe when Keltham dares to try on an intelligence headband, if he ever so dares, it'll be immediately apparent to him that this headband boosts every part of cognition that Owl's Wisdom didn't boost. But Keltham is guessing that this will prove to not be the case.
Consider, then, the world in which Golarion has a Detect Intelligence spell and a Detect Wisdom spell, but these are only 3 out of 7 components of cognition.
It's not the kids with highest thinkoomph who get tracked to be wizards. It's the kids with the highest Detected Intelligence.
It is of course famously true that in humans (and describing humans is what the concept of 'thinkoomph' is all about), most things you can measure about thinkoomph's components or outputs will all correlate with each other quite a lot. The kids with Intelligence 14, which Keltham thinks was supposed to be the wizard-tracking threshold, do tend to have Wisdom 12 rather than Wisdom 10. But if you were looking not-at-random at somebody with Intelligence 14, selected on high Intelligence, and asking 'what are the rest of their thinkoomph components like', then the rest are probably more like what their Wisdom score happened to be.
When you select on kids with high Detected Intelligence, you're not just selecting for kids with high general thinkoomph levels that produce high Intelligence along the way, you're selecting for kids whose Intelligence is unusually high compared to the rest of their thinkoomph. That's why the Wisdom comes out as 12 instead of 14.
Dath ilan has heritage-optimized itself over generations in full awareness of how all these measurement and optimization gotchas work. They are doing their best to measure real-world results broadly, and doing genetics and statistics to them. Dath ilan does not want to end up testing some weird projection of thinkoomph that originally started out correlated with thinkoomph, optimizing over this weird projection, and ending up with optimized things that have much more of the weird projected quality than they have thinkoomph. Dath ilan wants actual thinkoomph and is explicitly not pursuing it the stupid way.
So you've got your kid with Intelligence 18 and Wisdom 14 and they get wizard-tracked and get a +6 intelligence headband or maybe, if they become spectacularly successful, a relic with +6 Intelligence and +4 Wisdom, and if they're incredibly insanely successful, they get 2 or 3 layered Wish spells on top of that. They end up, say, with 27 Intelligence and 21 Wisdom; in dath ilani terms, those subcomponents of thinkoomph would now be at +4.5sd and +1.5sd respectively.
But their other 4 out of 7 thinkoomph characteristics are still around 14; or in dath ilani terms, if the scales match, -2sd. Golarionites don't know how to easily measure these other components; they don't try to boost them; they don't think about them.
This sounds a lot more like a model consistent with Golarion, than the model where anyone with +6 thinkoomph has literally ever existed here. You don't need training to be a Keeper at +6 thinkoomph, you just are one.
Inside Keltham's mind this is all a much shorter and better-chunked thing to think; what he thinks, roughly, is 'Hey maybe they got Goodhart's Cursed on Intelligence and Wisdom metrics'.
Only Keltham's actual thought is that thinkoomph is the underlying true value; Intelligence and Wisdom are imperfect proxy measures of thinkoomph; optimization over Intelligence and Wisdom will select not just on thinkoomph but on upward divergence of measured Intelligence and Wisdom scores from underlying thinkoomph scores; that this applies both to selecting students for wizard-tracking and for boosting them with Intelligence headbands later; and that this will of course produce people who may detect as +4 Intelligence and +4 Wisdom but who started with something like -2 or -1 underlying general abstracted-correlation-of-thinkoomph-components, and now have something more like +1 final-optimization-power as a result of all that Intelligence and Wisdom boosting.
Nobody with +6 thinkoomph has ever walked through this place. They'd shred it around themselves like tissue paper.