You guys are just too good! ++everyone.
So shortly after I posted I tried

my @la;
foreach my $s (sort keys(%sections)){
  push @la,a({-href => "/$sections{$s}"}, "$s HOME");
}
print join(" |",@la);
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which does the trick, and it seems the loop is just a longer (and perhaps clearer) way of saying (as Mr. Foy so eloquently stated)

my @la=map { a( {-href => "/$sections{$_}"}, "$_ HOME" ) } sort keys %
+sections;
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As far as formatting of the source HTML, I tend to do a

$\ = "\n";
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near the top of just about every program, especially CGI scripts, for precisely the reason Mr. Foy stated. As the documentation for CGI.pm states,

"By default, all the HTML produced by these functions comes out as one long line without carriage returns or indentation. This is yuck, but it does reduce the size of the documents by 10-20%."

(my emphasis)

Thanks again,
Terrence