You hear the greats talking about it at some point, stay relaxed, loose muscles are fast muscles, etc etc.. We talk about creating stretch, creating tension, resistance. Can too much be detrimental to powering your swing? For example, how much tension/resistance do you want to build in your backside when the COM progresses forward? As much as possible, or can that lead to getting to tense? I understand you want to be explosive, but the pros look smooth to me, quiet power.. with the odd exception.