I often do something similar to what you are doing, but with a callback function on the replacement side, together with the /e (evaluation) modifier. 
#!/usr/bin/perl -w
use strict;

my $main_template = do { local $/; <DATA> };
$main_template =~ s/%%([^%]+)%%/Callback($1)/ge;
print $main_template, "\n";

sub Callback
{
    my $field = shift;
    my $val;
    our $keycount;

    if ($field eq 'searchresult') {
       $val = 'SEARCH RESULT HERE';
    } elsif ($field eq 'premiumlistings') {
       $val = 'PREMIUM LISTINGS HERE';
    } elsif ($field eq 'keywords') {
       $keycount++ ? do { $val = 'FIELD(SEARCH)' } :
                     do { $val = 'FIELD(KEYWORDS)' };
    }

    return $val;
}


__DATA__
<HTML>
<BODY>
%%keywords%%
<BR/>
%%searchresult%%
<BR/>
%%keywords%%
<BR/>
%%premiumlistings%%
<BR/>
<BODY>
</HTML>

[download]

And the output -
<HTML>
<BODY>
FIELD(KEYWORDS)
<BR/>
SEARCH RESULT HERE
<BR/>
FIELD(SEARCH)
<BR/>
PREMIUM LISTINGS HERE
<BR/>
<BODY>
</HTML>

[download]

In reply to Re: Multiple HTML field names by Roger
in thread Multiple HTML field names by Dente

Title:
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