As a thought/my $.02 on the belt issue...
Belts don't "take away" from the stimulation of the prime movers. You could technically argue they do the opposite. I mean, does your core "lift" the weight in a squat or deadlift? At least in principle, no, the spinal position remains neutral while the prime movers (some combination of the hip and knee extensors) do the work. This is completely different compared to something like a squat suit or bench shirt, in both of those cases the elastic energy is being stored in the material itself, but no such relationship with the belt exists, it can't store elastic energy in that way (obviously).
So the fact that you can lift heavier with a belt pretty much translates directly to the prime movers actually being capable of moving more weight. How? Well the weak link in a squat or a deadlift isn't just the prime movers, the "core" acts to transmit the force produced from the lower body to the bar via a rigid midsection. A belt allows your abs to brace against something, and indeed, research has shown that ab activity is actually HIGHER with a belt. It's actually a little more complicated than this, as it's not just the ab bracing but the whole midsection "filling" against the belt and creating, in effect, an artificially larger midsection. The net effect = increased intra-abdominal/intra-thoracic pressure and consequently a more stable midsection. A more stable midsection = prime movers capable of generating more force. Interestingly, some other activity wearing a belt might be a little lower (e.g. obliques), however.
So what's the downside of belt use? Some people (e.g. Mark Rippetoe, Jim Wendler, the 70's Big guys) don't think there really is one, that belted strength will transfer pretty directly to unbelted strength. Here is a propaganda piece on the topic:
http://70sbig.com/blog/2012/07/belts-redux/
My concern is that a belt, while not exactly a crutch, does actually change the nature of midline stabilization (i.e. stabilizing the core), i.e. alters the recruitment pattern. In terms of what might "transfer to real life" better, obviously not wearing a belt is more similar to that. There are some people in the strength game that I respect greatly (e.g. John Broz) who feel like the belt is a crutch, and don't train their lifters to use one. Here's Mendes' legendary beltless, 800 lb high bar squat:
https://www.youtube.com/watch?v=WK7m6I5m6gY
A lot of people will be like "LOL BUT HE GOT POPPED USING HGH." Yah, everyone who uses HGH magically gets an 800 lb high bar squat k thx cya bai.
It's honestly a fairly hypothetical argument, and I can see both sides of the debate.
edit: some clarification on the technical stuff.