Never flown a Chipmunk, so can't answer your questions, but a couple of comments on 4)
The poor visibility on final which is experienced in many aircraft is nothing to do with the aircraft being a taildragger. When an aircraft is in the air, it doesn't care where its wheels are. If you sat the pilot in the back seat of a C172 or a Warrior, moved the engine up a couple of inches, and ensured the windows didn't come down any lower than shoulder height (and preferably much higher), you'd have exactly the same problems.
I have a few hours in this type of aircraft (I mean taildraggers where you can't see the runway on final - not spam-cans with the ridiculous mods I just described!) but not very many. I wasn't taught to fly a curved approach. I was flying out of an ATC field, where a curved approach would have been very inconvenient if ATC required an extended downwind (or even a "normal" downwind).
Instead, the technique was to come in very high, and make a steep approach - power off, and maybe 10kts faster than you want to be "over the numbers". The nose-low attitude then allows you just enough view over the top of your pax (or instructors) head to see the runway. Generally, the type of aircraft where this type of approach is required doesn't have a problem bleeding off the extra speed when you're on very short finals.
Another possible technique would be to side-slip down the approach, so you can see the runway out the side of the plane. Both these methods allow you to fly a straight track on final, and fit it with other traffic at (civilian) airfields much better. Any thoughts on this from pilots who fly this type of aircraft regularly would be interesting...
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