Thanks once again for such a thoughtful comment! I like that you always add to the topic :-)
About the only time weight/strength doesn't seem to come into play as much, is about 3-5 minutes into a role with someone who has not trained at all. Eventually the size and strength advantage fades away, and they are now fish in shark infested waters with any blue belt and above.
Even I have experienced this with some new spazzy blue belts, once they get tired you can dominate them simply because they are so short of breath they can no longer move let alone think clearly, hehe...
I believe a clear proof that BJJ works is that women who have higher ranks are definitely capable of handling people who might be bigger and stronger, but are certainly much less skilled/knowledgeable. There is a newly minted brown belt girl in our team that even bigger guys who have been training for 3-4 years have a lot of trouble dealing with; they say that sometimes even if they make use of sheer strength to try and overpower her, they just cannot dominate her and often end up bow-and-arrowed, haha!