Naruto Thread (Spoilers For Sure)

I don't think so or there would have been no point of the curse mark at all.

When Sasuke used the 3rd CHidori against Gaara, curse mark came out to help him. He got extra chakra because of it, otherwise it would have backfired, and it was obvious the cursemark helped him because he got marked.

I definitely don't think he kept extra power because of the curse mark, but it may have helped him reach higher levels of Chakra, which is what you said. But certainly not the full amount the curse mark was worth. Compared to normal training though the curse mark was worthless in my opinion and didn't help that much.