g1smd - 2:36 pm on Jun 29, 2013 (gmt 0)
Some years ago, jdMorgan showed that for server under high load, these things did make a difference.
The fact that .* is "greedy, promiscuous and ambiguous" should serve as a warning that it is often not the right thing to use.
I'll repeat again. When designing a RegEx pattern, aim to have it parse cleanly from left to right in a single pass without any back-tracking.