A signature problem

So I have this email signature. Actually, I have about three. One is the somewhat standard signature I use for all ATPM-related correspondence. The other two are personal sigs which vary only in the email address contained in the signature. One is for the address at this domain, and the other is my Gmail address.
I have set up these signatures with keystroke shortcuts in TypeIt4Me, which I encourage you to check out. Without going in to too much detail, these three signatures are shorthanded “asig”, “gsig”, and “rsig”, and this works very well. For the most part.
I seem to have this memory muscle problem with the last abbreviation. The other two I can rattle off with nary a conscious thought going from my brain to my fingers on the keyboard, but the last has proven to be rather elusive. Instead of typing “rsig” I find myself typing “risg” instead. I even did it in the previous sentence, and had to backspace and fix it.
The obvious and lazy solution is to create a new abbreviation in TypeIt4Me that automagically puts in the proper signature when I mistype the actual abbreviation, because there’s little chance “risg” will ever be a real word in the English language, but that still doesn’t help with why I’m mistyping it in the first place. Bizarre.