[Tagbert]

conversely, what is the case for single letter names, even in the situations you bring up? Why would someone chose to use single letter names?

[sokoloff]

There are many cases where a single letter variable name is clearest and easiest to read.

My loop iterators are mostly single letter. A coordinate is likely to be an x, y, or z. A unit vector aligned to an axis will be i, j, or k. A point is likely to be p. A vector data structure v. The first transformation of a variable x is likely to be x’, the second x’’, etc.

[fortituded0002]

All these are all math terms and standards which are defined outside of code.

I think there's something to that - if it's a common enough convention they use it. But if not, don't make it up.