I picked up one of these over the weekend and will be headed out in a few to see how it handled the job.
https://www.4wheelparts.com/Air-Compressors-Air-Tanks-Air-Accessories/Smittybilt-2-54-CFM-Air-Compressor-2780.aspx?t_c=89&t_s=566&t_pt=100437&t_pn=S/B2780Reading some of the links that Gnarly posted a wider tire doesn't have more traction, it simply give you a higher chance of achieving maximum traction. This is because the friction force is independent of the surface area.
http://www.dummies.com/education/science/physics/how-surface-area-affects-the-force-of-friction/What's interesting is that for sports cars going with wider tires give you a better opportunity to achieve maximum traction, but it allows a softer rubber compound to be used without wearing out any faster.
This, of course, is all things that could be shown in a lab environment. The test I suggested earlier to measure how much pull a given rig could produce should, in ideal lab conditions, result in the same results at street pressure and aired down all other things being equal.
In the real world this is often not the case. Another experience that my dad had was a nearly complete loss of traction from his BFG KMs on ice as they were nearly worn out. The lugs lost their ability to flex and as a result couldn't not maintain traction on ice. It was a drastic change from when they were new. The rubber compound didn't really change, but the physical shape of the lugs had changed no longer allow them to have any flexibility.
When airing down off road you're increasing the surface area which increases the chances of achieving maximum traction while also making the treat more flexible which allows it to maintain contact longer which make it more likely that one lug won't lose traction before another engages. Then you have the other benefits of airing down that include a softer ride, less impact load on your entire rig, better protection for the tire itself (in most cases).
If 300k is looking solely at the equations his argument is valid for a physics test, but because there are a lot more factors to be considered in the real world it doesn't translate to the point that the rubber meets the road.
