It's really hard to pass off the post so late in the route, especially when that same post is so important for the CB to cover against other concepts like mills or double post. I think most coaches would rather keep the CB on the post and have the nickel/will carry the wheel. That's more consistent with the match rules too, if you think about a wheel as a double move route that is flat-then-fade. If the #2 just went to the flat, the nickel/will would have that assignment, so when he continues vertically, the defender just stays with him. It's still a difficult assignment, which is why post/wheel is so good against quarters. Ideally, we'd play a different coverage against it, like what Saban/Patterson call Clamp/Cover Blue. That would have the CB take #2 as soon as he goes to the flat as part of the wheel route, but it would isolate the safety on the post, which we may not want with our personnel.