I have to say that whilst the majority of the op post was just bull**** there is a valid point in there.
Firstly, the only way to build muscle mass is to lift heavy and fail at low reps. This is the ONLY way to ensure that you tear the muscle adequately without failing due to fatigue. You CANNOT build the muscle without tearing it, as this is the only way to force your body to adapt by creating more muscle.
Secondly, you HAVE to eat a hell of a lot to build. This is because not only to you have to replace all of the energy that you expended lifting, as well as providing enough energy to actually build new muscle, which might I just point out takes a lot of energy, hence eat a lot, as calories are after all just a measure off energy.
Thirdly, yes for most people body weight exercises are enough, but this is because that is lifting heavy enough to tear the muscle for them.
Fourthly, if you were increasing the weight you were lifting every week, then you weren't lifting heavy enough to begin with. However, I do agree that form is the most important thing, but only for the first 2 sets. Your fail set should have around 80% acceptable form. And, yes many people do go to the gym and lift too heavy, swinging there whole body as they try to curl a stupidly heavy weight, and yes that is counter productive. Hence, why I operate on a 'leave your ego at the door' policy, lifting as heavy as I can for 2 sets with perfect form then increasing the weight and failing in the next set.
Finally, with regards to the joint problems. Yes this is an issue, but it is kind of an 'acceptable losses' situation. If you are going to lift weights heavy enough to tear the muscle then it will put pressure on the joints and cause aching. This is common ammongst anyone who actually lifts decent weights regularly and cleanly. Most of us who do actually end up taking supplements to help joints, cod liver oil, or glucosamine and chondritin are my two favourites. But like I said to build effectively you have to make your body thing that it is in danger and has to adapt by building more mass to survive, effectively continually pushing it out of its comfort zone.
And anyone who seriously builds will admit that they won't see continual progress week in week out. The op probably only does because he isn't actually building at the muscle head, his muscles are just becoming more dense and efficient.