However, when you learn to stop worrying and let the runtime decide it's so much nicer. It turns out that people have already optimised the framework, so at worst it's just as fast as the code I wrote. At best it's faster because the framework knows more about what it's capable of.
The biggest thing to realise is that while you can easily make things perform well in isolation the runtime can look at the bigger picture. There's no point making an operation run in 300ms if it blocks all other tasks on the server, when it could run in 600ms and allow everything else to keep going.
