I don't really care enough for you to change that, but it's just a statement of preference. If there are other instances of it in this codebase a lot of them are probably in external modules or just things I haven't had reason to edit myself yet :)  I find just "i" as a variable name to be difficult to distinguish sometimes.

Sometimes I see people use "ii" and "jj" and that seems to work okay except when they start mixing them with just "i" and "j"