Yes, I thought 'oh this has been done carefully' when I read the bit about considering `\var` uh.. variants, but I was surprised that that consideration wasn't grouping them together - counting sigma with 'var sigma' for example.

Are they ever treated as different? Here's a whole lot of \vartheta on Wikipedia for 'theta function', for example: https://en.wikipedia.org/wiki/Theta_function#Jacobi_theta_fu...

I always thought it was just like having both a 'double-storey' and 'single-storey' 'a' available in the same font.