[teh_klev]

LINQ is a great mechanism for expressing complex operations in a succinct manner. Sure, LINQ may not be a magic bullet and can be abused, but you know the old adage about premature optimisation. Perhaps you could elaborate on "It has some serious pitfalls.".

[hvidgaard]

I didn't write the post you responded to, but I can tell you of the main pit fall I have encountered. By far the worst is evaluating the same enumerable again and again by mistake. It don't show up in unittests because they use small data sets, but as soon as you do any kind of load test or put it into production it's painfully slow. The solution is often very simple, but you really have to get dirt on your hands before you recognize where it is a problem.

[kryten]

See https://news.ycombinator.com/item?id=6026280