Bod, for future reference, note that B::Deparse is a handy way to see how the Perl parser interprets your code. Running:
> cat bod-oh-my.pl
(my $pname,my $sname)=split / +/,$rname,2;
> perl -MO=Deparse bod-oh-my.pl
my($pname, $sname) = split(/ +/, $rname, 2);
bod-oh-my.pl syntax OK
verifies that your razor-sharp Perl intuitions were spot on today.
Update: In case you're interested, -MO=Deparse feels like an old friend to me,
after using it time after time while testing and verifying Acme::EyeDrops and when
playing golf. :)