I mean you can try if you want, I don’t really understand all the technical details of AHK so maybe I’m doing something wrong. I would be surprised if simple 3 SENDs one after another worked and without blinking but there are many configuration options like key delays and stuff maybe I’m missing something. I’ll check it myself too
I’ve got blinking with 
a::
Send {t}
Send {1}
Send {t}
Return
[edit] Ok, no blinking if you precede this code with
SetKeyDelay, 0
Btw mods sorry for this off-topic in off-topic, it could moved to the following thread