Michael, I already discussed this with Lain_13 - he tends to micro-optimize things that are not worth optimizing. The matching performance that we have now is very good and the delay isn't really noticeable. Any complication of the current algorithm will most likely cause a larger delay than the eight filters in EasyList currently using "http" keyword.
Btw, not sure whether Lain_13 shared that link with you - http://pastebin.mozilla.org/?dl=1064160
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