Identifying words with valid double characters makes this trickier. I'd start with something like: 
while (<INFILE>) {
    s/([A-Za-z])\1/$1/g;
}

[download]
That's not an ideal solution, but it's a brute-force 80 percenter.

In reply to Re: Removing characters by chromatic
in thread Removing characters by TStanley

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