So you agree with Ted, have little real pinball experience and haven't tried too many of these tables but want to comment on odd behaviour? OK sure, you are entitled to share your opinion.
But as I said in other parts of my post, I do have some experience, including two hours just recently of playing real pinball, everything from 60's up to JJP's WoO. In those two hours, I saw some back spin (enough to go down the table, then back up as if a magnet threw it) once or twice. I can't play a single ball on a single table with the physmod without seeing it. I also watch hours of PAPA video, from tutorials to the competitions and I almost never the ball behave like it does in the physmod. So I may not have as much experience as some, but I do have some; and just because I may not have experience playing doesn't mean I've never watched someone play and noticed in difference in ball behavior.
I can't understand why you would expect unpredictable behaviour with the introduction of spin and for tables to play harder. If physics are improved the result is more predictable behaviour even when additional variables (such as spin) are introduced. Unpredictable behaviour means the physics are worse and the recognition of unpredictability is clear evidence of that.
So, because you understand physics and you've had however many years of experience that you've been on this planet, you can make any physical act happen exactly the way you want it? Not even robots can do something perfectly because of the unpredictability of everything that is a part of physics. In a system that doesn't implement real life physics accurately, it's easy to get expected results; but because there's always something that can't be predicted (an insert get shaken out of place, a waft of heat from a bulb that's been on too long, a bang on the machine that separates the leaf switch ever so slightly causing the firing of the solenoid the be nanoseconds later), better implemented physics can make things more un-predictable if the previous system used too many constants. The only way anyone has ever been able to program physics has had to program some degree of randomness since that how it appears to humans; leave out too many factors that influence a system and it becomes too predictable, put in too much randomness and then it's just a game of chance. Point is, it's possible for better implemented physics to introduce "randomness" to a game if the previous system was poorly implemented.