You are right. I have added complexity, but performance was more improtant in my case.

Also, I did not touch LINQ to Entities which is completely different thing. Performance difference between EF and Raw sql will be obvious on larger sets of data. EF's deserialization is quite slow, comparring to Dapper.

Again, my main point is that readable code should be writen by default, and optimizations applied only if necessary.

I've showed how exactly LINQ to Objects impacts execution and what we can do with it.