You've probably heard them: “Always use a StringBuilder!”, “IEnumerable is 2x faster than IEnumerator!”, or similar claims. The internet is full of advice, benchmarks, and "best practices", but how many of them actually hold up under scrutiny?

In this session, we’ll dissect some of the most persistent and misleading programming myths floating around the C#/.NET community. We'll use these tales as an excuse to know what is really going on: how string concatenation really works, what the garbage collector is actually doing with your objects, why List< resizing isn't free, and how benchmarks can lie.

By the end of the session, you’ll not only be able to spot shaky advice from a mile away, but you’ll also have a deeper understanding of how .NET behaves under the hood.