Sorry if this is against the rules, I really don't know, but I don't see why it wouldn't be allowed.
At TTi you have a seed bonus. 72 seed hours lets you give 5 gigabytes upload to a friend, while 168 seed hours lets you add 5 gigabyte upload to your own account. What I'm asking is a simple exchange. Someone adds 5 gigabyte upload to my account, I do the same with theirs and we don't have to spend the extra hours seeding.
I don't think it's breaking any rules, but if it is just tell me and I'll close it.