Now that you mention grammar checkers, the following analogy suddenly occured to me: strict is to a spellchecker as warnings is to a grammar checker.

In which sense? In my experience, both strict and the spelling checker point out real problems at least 90% of the time, making them highly effective and not too annoying. But warnings and the grammar checker are right less than 50% of the time, which can make them too annoying. ;-)