Neither keyboard intruments not fretted string instruments recognize more than 12 notes/keys per octave.

That is, in the context of any instrument upon which one might affix a capo, there is no reason to even introduce the confusion-inducing concept of the very slight (and essentially theoretical) difference between, say, C# and Db. On a "capo-able" instrument like the guitar, such differences do not exist in any practical sense.

When attempting to instruct someone who has not yet grasped the relatively simple concept of naming the key he/she is playing in when employing a given set of chord shapes along with a capo placed at a given position, muddying the waters with advanced music theory about tempered scales, etc., is counterproductive.

So quit showing off if you can't be helpful!