Taking out the capturing parenthesis around the whitespace helped a lot. Here's the benchmark results: 
Benchmark: timing 50000 iterations of regex, split...
regex:  3 wallclock secs ( 3.03 usr +  0.01 sys =  3.04 CPU)
split:  4 wallclock secs ( 3.79 usr +  0.00 sys =  3.79 CPU)

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In reply to (chromatic) RE: (jjhorner)Regexp glitch while parsing record in CSV by chromatic
in thread Regexp glitch while parsing record in CSV by greenhorn

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