Disney is letting us 'lucky' people use FP-....because we don't get to opt out and go with FP-. WHO in their right mind would CHOOSE to be a tester with only 3FPs in 1 park?!

NO way would I agree to that.
This was the trouble I had. I was glad to be testing but 3 FP, in 1 park and oh yeah only for SEVEN days. When you go over 20 FP it says "you've used all your FP thanks have a magical day AP holder".
I enjoyed the FP+ it was kind of fun despite glitches my MB had remembering my AP, and remembering to let me in my room once (a couple of hours in a couple of lines trying to fix 3 issues).
But 20 FP total (really 21, 3 FP x 7 days really), 3 in one park per day, for a max total of 7 days, during a 2 week trip is well... disappointing.
I think it's why TDO is allowing the double-dipping for now to mask these limitations. Or to look at it another way, perhaps they will use these long testing periods to gather statistics and perhaps to tweak these upper limits (I can hope).
When the testing is over, if not adjusted those limitations for anyone staying more than 7 days, an AP holder will especially feel it. MYW ticket holders might not have the 20 FP limit, in which case there will be fewer AP holders next year, two 10-day MYW packages might cost the same or more than an AP, but will give more "value" if your FP is not limited to 7 days. It will be harder to calculate the break-even point of the AP, for me certainly.
I heard they may up the limit for AP to 28 FP per quarter, but still that's about 9 days of FP. 2 week trips would mean days with no FP+
More than 12 or 13 days in the past was an easy cutoff for me to estimate to justify buying an AP, but what is that cutoff now? It will depend on how much I value any FastPass+ additional to whatever the limit is, versus the limit (or non-limit) available in from multiple MYW tickets, not as easy to quantify in dollars.
The future of being an AP holder and park-hopping, I'm not sure I see yet what those plans are, but it's beginning to appear one outcome planned for us was this:
Former AP holders spending more $ on multiple MYW packages, just for the perceived value of attaining more than the limit of 20 (or 28) FP+ in a trip? The incentives to be an AP holder just keep diminishing for a non-local.
PS - I won't go into how this will affect locals because I'm not a local, but the value they get from AP will be seriously diminished by FP+ limitations.