The weight was a disadvantage. The sole reason he needed to lean on his opponents and clinch in the first place is because he was out of shape, not to mention his legs and reflexes were gone. And the weight differences weren't that big. Mostly around 5-10 pounds.
We'll have to agree to disagree. He didn't lean because he was keeling over, it was very strategic and very effective. It's not a knock on him but a credit as far as I'm concerned. Also, the weight gap wasn't huge but still meaningful. It was a larger weight advantage than Wlad has had in his defenses.