Since the last update on this thread, I've done some research regarding effects of dough kneading style, time and dough method on the final product. During my humble efforts, I learned many things that I'd like to summarize in the following points and I hope anyone reading it would assist if they find weakness in my understanding:
1. I found it very easy to understand the process of dough development by imagining dough gluten as a network of rubber bands; where mixing stretches and entangles those rubber bands and stores more energy into the network with kneading time.
2- As it's probably already known and mentioned even in this thread, you cannot compare mixers/mixing methods by the mixing time as I also learned that it is better to compare in terms of the energy delivered/stored into the gluten network. While equipment to measure energy stored into the gluten network is not available to home pizza makers, we can still get a feel for it by understanding the concept and how that effects the look and feel of the dough. The energy delivered is a product of the (mixing-method x mixing time) in relation to dough type (mostly hydration). This of course would mean that different mixers will always differ in mixing time to deliver the same gluten development keeping dough hydration constant. Also, the gluten development mentioned here is in the terms of elasticity/extensibility as you need to keep in mind that different mixing styles will also differ slightly in the texture of the dough (on the gluten network level) and the final product.
3- Regardless of mixing style/method, there are three things that I find constantly happening but at a different rate: Mixing, air incorporation and kneading(or gluten development). I found it is better to separate these three as different terms in order to better understand what's happening to the dough.
4- Mixing is basically is the incorporation of all of the dough ingredients which only takes few minutes in the initial stage of preparing the dough. During this stage there is not much happening in terms of incorporating air or kneading (developing gluten). By the end of this stage, the dough starts showing resistance as a sign of gluten development.
5- The other two terms happen in parallel, air incorporation and kneading (gluten development). Both, the amount of air that is possible to be stored and the gluten development; have a maximum. Luckily, it turns out that the stored air limit is reached before the gluten reaches full development. At the beginning, air is stored as non homogeneous, differently sized bubbles. As you continue kneading, air is continually being separated into smaller and more uniform bubbles trapped in the more-entangled gluten network. Stopping where maximum air incorporation achieved is what Tom refers to. As at this point, you have the maximum amount of air that you can achieve and yet, the bubbles are not 100% uniform, thus resulting in an irregular, non-bread like crumb. If you continue past this point you start making bread. If you further knead and develop gluten, you will have a bread dough with a very tight gluten network that hinders expansion. If you further knead! the rubber bands cannot take more energy and break, thus letting some air bubbles joining again by the means of a damaged gluten network which might produce a slack problematic dough after fermentation.
6- I have also learned that the dough hydration gives another dimension into gluten development. If you visualize a high hydration dough as few rubber bands swimming in a lot of water, you can tell that an improper kneading style and speed might not have proper control in order to store energy in them. A regular KA mixer will simply stir those bands around in water doing nothing because you're aimlessly putting energy that is not being stored; while if you knead by hand, you have better control and can make sure that the gluten network is properly being stretched and storing energy. This is the reason why diving arms mixers are preferred in high hydration as they simulate the hand of the dough making person. Also, I believe this is why Marco in one of his posts said that in order to knead a high hydration dough, you will need a high speed spiral mixer. Spiral mixers are believed to be efficient in delivering energy into the gluten matrix, so combining that with high speed will even improve kneading. This is also the reason why spiral mixers are believed to produce a tight dough in normal hydration levels.
7- Lastly, combining the previous points along with fermentation, cutting/balling and proofing will further change the crumb. If you prepare your dough, directly cut it, ball it and then fermented/proof all the way to bake; the internal crumb structure will mostly be maintained. Where if you bulk fermented for the longer time; then cut/ball and proof at the last stage til baking, this will effect the crumb greatly because the air bubbles are enlarged, full of CO2 and some will join together because of the weakened gluten network during fermentation.
I am sure that I missed a lot of information but this is what's present to me at the moment and thought it would deliver my understanding that I hope will help others in understanding mixing.
So Pete, yes...I agree that slightly under-kneading will produce the proper pizza dough

Saad