Joe,
For what you think you know....
1. A folded prop has the least drag.
2. Correct.
3. Correct. Dramatic is a relative term of course.
4. Also correct, in my experience.
Before answering the questions......your Emotion needs nothing to fly Intermediate....leave it alone. The need/benefit for braking (beyond an electric freewheeling) is dependant on many things....airframe drag, prop used, flying style, complexity of maneuvers, etc.
For your questions -
1. "Proportional" should mean the amount of braking is incremental based on the amount requested. RC cars have had this function for many years, and I believe some of the Schulze airplane ESCs have proportional braking (adapted from the car ESCs) that can be programmed so full idle is more braking than 1 click above idle, and 2 clicks above idle is the least amount of braking, and 3 clicks above idle would be the slowest possible idle (and I think the amount of range for the braking zone can be adjusted). I'm sure Chad will add to this if I don't have it right.
2. There is no criteria for speed in judging/scoring. However, there is the incredibly ambiguous "smoothness and gracefulness" criteria (which being so poorly defined I think should be eliminated from the judging criteria, but that is another topic). I would suggest that the best possible presentation would be one that is 100% constant speed. If the terminal velocity in a downline is faster than full throttle in level flight (let alone an upline), you will never be able to achieve constant speed.....ie, the "best" setups have slow downlines.....it is easy to speed up a downline (adding throttle)....it is not easy to fly the entire pattern at 100 mph, if that is what the terminal downline velocity is.
3. For me, I have a 3 position switch that is set for brake (normal flying), slowest possible idle (windy weather), and fast idle (stall turns and spins). I can always add throttle whenever I don't want the brake.
4. I don't think any of the ESCs will engage the brake if they are set for lowest possible idle (I know 100% the Castle will not).
5. I believe it is a particular ms.....that is certainly the case for Castle.
Regards,