Didn't read the link, but here is what I have seen:
SnoPros (race sleds) come with two, and they see big bump use.
Two in the rear DOES lead to bent/broken axles, depending on use and style. (The race sleds that come with two have beefy axles.)
I personally run two/convert them if they don't come that way, but I am more of a smooth aggressive rider than "beat the hell out of things" aggressive rider and I have never damaged a set.
Also consider, as said above, if you have time/money into occasional trips, the reliability is an issue. I personally don't trailer more than a few miles to ride, so if something breaks I just fix it and go back out the next (sometimes the same, lol) day.