However, I'm still confused as to why there is such a dramatic change.
That's easy. You change your original items in @messages, so after one replacement, there's nothing left to replace.

Add 

    my @messages = @messages;

[download]
at the top of each routine, and the difference becomes much less... Roughly around 22% of difference, just for the 2 extra substitutions.

In reply to Re: Strange benchmark result that has me totally confounded by bart
in thread Strange benchmark result that has me totally confounded by jpfarmer

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