Killing the bent-four-in-the-corner should come after filling dames (to remove outside liberties) and removing ko threats. If there are unremoveable ko threats, then whether or not one should try to capture the bent-four-in-the-corner will depend on strategic considerations.
Also, without unremovable ko threats involved, I think most reasonable players would simply just accept that the bent-four-in-the-corner is dead without having to play it out.
The difference between those two counting methods?
I learned the hard way that the score estimator is based on Chinese rules. Score estimator showed +0.5 for Black. After we both passed I lost the game with -0.5 points.