Oh, well... I see now, I'm stupid

You're right, I'm over a false problem. The error message I had was for the over ID, extra "<>" stuff... I was thinking that I had another type of problem here, that in fact is not a problem at all to Perl; not unless you wrote:

my $mystring = "ABC".<ID>."blahblah</ID>DEF";

That is a very different situation to...

my $mystring = "ABC<ID>blahblah</ID>DEF";

So I was in the clouds again (what a zurprize)