Right. Spell check is easy, rarely wrong, and east to correct via a "learn this word" option. Grammar checking is hard, often wrong, and hard to correct. That's why I either turn it off or learn that green squiggles mean "no problem." Unlike spelling, coding style is impossible to codify; it is basically "whatever the current Kool Kidz say," said Kidz are different every day, and they are almost never able to specify -- much less justify -- what they mean.

Either the problem's easy (spelling), corrections are ignored (squiggles), or the "solution" is an annoyance (clippy).