Ok Doctor Dave,
You gave me a lot of homework to do...I thought I was done with school. Gosh!
For your and the audience's convenience, I have color coded and enumerated my response. I hope that it is not made in excessive haste.
1) "because of the contact time being too long": already, it seems that you are conceding my point...that the contact time has an effect.
Typical cue tips have contact times in the 1-2ms second range, where differences do not have any important effects. But if you change the contact time significantly (e.g., by using a soft rubber tip instead, which is not suitable for playing pool), the physics is very different.
2) If you want to claim my statements are wrong (which make sense and agree with accepted theory): I feel that you are taking my skepticism of your claims personally. I hope I'm wrong, because neither a scientist nor a pool player should.
I was simply stating that if you want to be skeptical and propose alternative theories that go against current knowledge and understanding, you need to convincingly justify and test your claims. This is how science works. I won't do it for you because I don't believe the time would be well spent. This isn't spite, just honesty.
4) A soft tip does not provide as efficient a hit, so more cue speed is required to get the same CB speed and spin: Here, there is much room for discussion, as your compatriot and also resident scientist, Mike Page, has challenged you on this question. My response to this is: at the end of the day, the question is: what is the effect of the tip hardness on the amount of imparted spin?...all else being equal...i.e. cb speed and so on.
Mike Page has correctly pointed out that it might be possible to create a soft tip suitable for playing pool that might have a better hit efficiency than a typical hard tip also suitable for pool. I have not seen one yet, but I agree with him that it might be possible.
5) You can definitely get more effective sidespin with a slower-speed shot, especially with a below-center hit, either with a soft tip or a hard tip, using a drag shot: This statement seems to me to be beside the point. The question is: Is there a difference between what you get if the tip is hard or soft? Whether you hit high or low is irrelevant...the location is the same, the difference is the tip's material properties.
The statement is very much on point, because several people have suggested doing comparisons with the same cue speeds. This could give misleading results.