No contradiction at all.
Say you 'measure' a person at 42. Fine. First, that doesn't mean it's 'the' answer for everyone with the same physical measurement. There is not a single worthwhile fitter that would hold that as true. If you hold that everyone with that measurement needs to ride those bars, you are just.plain.wrong. In that sense alone, my original statement is true.
Moreover, that measurement is highly subjective. Some argue the measurement standing upright, some in a riding position, some from the outside edges of this, the top point of that, and so on. Add the variation that presents, and there is no way a rational person can say that there is a formula that 'works.'
So without realizing it, you are doing the fitting by eye and feel. Having a tape measure in your hand gives you a misplaced sense of confidence in what you are doing, and the impression in the mind of the person you are fitting that it's somehow 'scientific', but the fact is you are simply making a judgement call. If nothing else, you've made a judgement as to which so-called 'expert' you've chosen to believe. Your judgement has more effect on the outcome than your tape measure. Hence, it's no formula at all, simply judgement masquerading as a formula.
On the other hand, you are going too far the other way with the 'across the room' silliness. Obviously, gross measurements are useful to get one on the right size frame, and usually within a cm or three on seat height. And once saddle setback is worked out (KOPS is not at all meaningful for the purpose, while we're wandering from topic) gross measurements get within a couple cm's on stem length and bar width. But since those are incremental goods, 'close' is no answer at all.
Bottom line, measurements are useful for getting the right size bike. That has little to do with fit.
Sizing on bars makes perfect sense to me. There's only a reasonable range that makes any sense (no one needs 20 cm or 60 cm drop bars, for instance.) But it's not hard to find 36's if you really need them, and I've a pair of 48's should anyone ever find use. In the meaty part of the bell curve, even-numbered increments are plenty. Anyone suggesting that someone needs a 43 instead of a 42 needs to put down the crack pipe. Some increment is needed, but 5mm on either side is goofy.
The frustrating bit is when you do want a specific measurement in a specific model and it's not available. I could sell a bunch of K-wings if they made an honest 46.