Well exactly. He refused to walk through all Rahvin's intricate little traps, and went to the heart to have a one on one with him. This caught Rahvin by surprise and it destroyed him. He did the same with Sammael, who thought Rand would never dare just pop up in his city. Maybe you can't torture Semirhage but if you spank her, she'll break easily.

This is Rand's whole point with Graendal... to NOT play her game, which becomes a whole complex little subplot filled with proxies, wit and intelligence. He rather just punched her in the face and balefired the whole palace. That is NOT the way Graendal does things, which is why she's dead.

Not only that, but you yourself say that Rand uses brute force to defeat them. I would say that Graendal is the same. He admits he can't defeat her so he uses a massive amount of saidin to end the debate.