AFAIK the code between parens in the foreach statement is executed just once to obtain a list over which to iterate.
So yours is not really an optimization.
Update: i see now your and suaveant point as the inner loop get called multiple times: the original post was not that clear.

$|=$_='1g2i1u1l2i4e2n0k',map{print"\7",chop;select$,,$,,$,,$_/7}m{..}g