I think that a heavier cue can in some ways assist with helping or even making you stroke smoothly. Now, wether not that kind of weight will help you concerning CB action is another debate. I wouldn't suggest it's benefits to be used for anything other than a temporary training tool.
Ever pick up a light and flimsy stick and try to hit a rock with it? Pretty tough because with such a light stick, your swing will be erratic and choppy. Do it with a baseball bat, and the task becomes much easier simply because once you have a certain amount of weight set into motion, it takes more effort to change that motion. I think the same idea is what would possibly help with a smoother stroke when it comes to a heavier cue.
dave