I'm not entirely sure where you're trying to go with this. IMHO, it'd do nothing but complicate mIRC procedures.
Aside from something like genius_at_work's example, you could just do something like:
alias dothis2 {
var %test = $1 $2
return $+(Test=, %test)
}
Like I do with my socket scripts:
on *:sockopen:test:{
var %s = sockwrite -n
%s GET /something.html HTTP/1.0
%s Host: www.test.com
%s
}
Maybe I'm missing what you're trying to do that would require said "static" aliases.
(Btw, when I use an alias to do some repetive things, I generally just: alias -l _somename { })