Ok, I'll try again. If You are flying a, let's say, VOR APP for runway 16 with circling 34, You will level off at the circling MDA and fly the circuit, we are all happy with that. What You can't do if You are flying a CDFA is level off somewhere above the VOR MDA, reach the MAPt and then dive down to land on runway 16 (aside from the fact that You will probably bust all kind of stabilisation gates).
I don’t think anyone is suggesting that’s a good idea, in fact I understand the original question was about whether it was possible to avoid that scenario by using alternate means.
Having said that, You can't fly a VOR APP for runway 16 and then circle for... runway 16 ! There is no legal provision to back up such a decision. You can fly either the published IAP (VOR in our scenario) or fly a visual.
That’s the interesting bit: you can fly a circling approach off RW16 to RW14, 18, 26, 33, 04, etc. which may require extensive manoeuvring if there is a sector you can’t circle in, or a circuit direction you need to follow. The main issue is staying within the prescribed area.
As I posted earlier, I don’t think doing an extended circle in conditions that are not good enough to give you a reference at MDA off an NPA is something I’d want to do, mostly because the chances of success are low and NPA/circling flight carries greater risk than most other types of approach. The technical question as to whether it is *allowable*, I’m not so sure. I don’t see a
prohibition of circling onto a runway, just because it happens to be somewhat aligned with your IAP. Some approaches are either not aligned with anything (see above charts) or dump you in a position where landing straight ahead is not feasible, even though the runway is right there...