I wouldn't use "with" in most situations, but I like it in the testing code and for some DSLs, as it makes things more readable (again, personal style). I thin

I wouldn't use "with" in most situations, but I like it in the testing code and for some DSLs, as it makes things more readable (again, personal style). I think that once you start optimizing performance problems you need to 1) measure things anyway, and 2) fix on a case-by-case basis. (Don't optimize prematurely, etc.)