This article is a good analysis! A few things I noticed while reading that may be useful (mostly really basic stuff, since obviously I'm not in the profiler wor

This article is a good analysis! A few things I noticed while reading that may be useful (mostly really basic stuff, since obviously I'm not in the profiler working with the code). Easy Win #1 could have been passing 2 as the second argument to the first call to String.Split, which would have sidestepped the "2 calls to split" problem. It's worth pointing out that Easy Win #2 has a bug, because you said you wanted "MNO" lines, but now you're also going to pull in "MNOX" lines. You should probably use StartsWith("MNO,"), since this would have behaved the same.