It's not my responsibility to direct you to where I have provided proof since you stepped into the debate you should have read all the posts regarding said point of the debate.A great deal has been written and said about the burden of proof, and certain misconceptions have arisen about the duty of the affirmative. The rule is simple:
Rule 5a. He who asserts must prove.
This principle applies equally to the two teams. Of course, the affirmative must show that its plan is desirable, which means that it must show that some benefits will result; otherwise it has failed to give reason for adopting the plan, and has lost the debate. The commonly heard statement that "the affirmative has the burden of proof" means that and nothing more.