It's interesting to me because taking "remember" and getting "remmy" strikes me as something a hearing culture would do. From a culture not based on oral communication, I'd expect something more like rmbr (A friend of mine expressed this too - I don't want to steal her ideas.)
I don't know if that makes sense or not, but for people who mainly speak and hear, to take a word and shorten it to something that sounds sort of like the original but is easier to say (and the speaking habit of changing things to a more casual form, which can involve tacking a "y" onto the end) isn't surprising to me. But how that would develop out of Deaf Culture kind of blows my mind.
When I force myself to really look at how we (hearies) talk, unless you're speaking really slowly and formally, remember kind of gets mashed into something like "memer". So it's different, and that's not odd for two different cultures to develop different variations in an overlapping language, but my brain still gets stuck when I try to think of how "remmy" might have happened.