A must watch YouTube video on stylus in the groove!!!

Google Applied Science LP you tube.  Should be right at top.  Look at those grooves and how the needle is Bouncing!!!!  Now explain how important antiskate, null points, etc are.  If you thought your stylus was running parallel to the smooth groove walls Well so much for that.

This guy is selling nothing in this video.  No hypothesis to let his ego get in the way and no conclusion.  Well  I thought some of the more technical guys might get a bang out of this, regardless if it might make you rethink  your own hypothesis.

Enjoy the ride
I reluctantly stayed at Motel 6 once and I have to admit it wasn’t that bad....thanks Tom
hahaha, it's even more fun now
My name is Tom. No harm has yet come to me due to this thread.

Now, what are you guys going on about? :~)
I watched the video of Peter’s talk at RMAF end to end. Very interesting. I have a lot of respect for his knowledge, expertise, humility, and kindness. He is really exploring the dynamic interface between stylus and groove in a meaningful way. He makes a compelling case for MI designs but at the end of the day I wonder why there are so many MC designs that sound at least as good as one of Peters cartridges. Case in point—owned an AT ART9 that was at least as good to my ear as the twice as expensive MIMC Star—in some key parameters better. If you accept Peters thesis this should not be the case. 
Ledermann is just selling his stuff and distorting reality to do so. Like any good salesman he has made it look.....compassionate. I love how he takes the biggest old antique moving coil assembly to compare with his moving iron. A modern one is significantly smaller and lighter. Moving mass is important, moving effective mass is even more important. Since the masses we are talking about are right next to the fulcrum they are much less important than the mass at the end of the lever (the stylus).
The best manufacturers have gone to great lengths to minimize the mass at the end of the cantilever by creating new ways to bond a naked very small diamond to the cantilever removing as much mass a possible. Of course Peter does not mention this. It is far more important than what happens at the other end. As far as "Jitter" is concerned it is just a marketing term for miss tracking. 
Name me one reviewer that uses a Soundsmith cartridge as their reference. I have not seen one. I have never owned a Soundsmith cartridge because I have never seen a series of reviews that get me interested. Peter's BS is certainly not getting me interested and the condition of his office really scares me away. Sorry MC, you loose me on this one. Go get yourself a Lyra or an Ortofon. Even a Clearaudio or a Koetsu if your tonearm is big enough.