It's all fun until you get something like FIGHT where the last four letters are right and have to just guess from LIGHT, MIGHT, RIGHT, SIGHT, TIGHT, WIGHT, anything I might have missed, and there's no way to use any strategy and you just have to randomly guess and hope you guess right.

I can see that happening, although for some reason it hardly ever does with my usual guess strategies. I've only had one word result in a few candidates. The fact that it happened immediately and almost unavoidably in the nerdle made me think this really wasn't for me.

This situation is technically possible, but I'd be surprised to already have 4/5 letters, and not have already tested R, S, L, or N (N from NIGHT). There are all one point scrabble letters after all. I could see myself needing to roll the dice on MIGHT, TIGHT, WIGHT.

You can guess WARMS, which will either give you the answer (to input on the next try) or eliminate 4 of the possibilities, leaving only 2 to guess.

That's a best case of 2 additional guesses and worst case of 3 (expectation of 2 1/3) which is better than your strategy, which has a best case of 1, worst case 6, expectation 3 1/2.

That's true for regular mode, but WARMS would be an invalid guess in hard mode once the last four letters have been established as IGHT.

The comment I replied to started with "You should give hard mode a try." In hard mode, WARMS is not a valid followup guess.

TIL about hard mode. That's just how I've been playing naturally; force use the found letters in subsequent guesses.