The fuel for change often comes from our own basketcase-ness. Once you recognize an issue, you end up with a rather intimate understanding of the problem on multiple levels: emotional, intellectual, social, etc. It's exactly that deeper understanding that allows one to see it in others, and lend them a hand - at least once you learn to keep projection out of the equation.
Put another way, the more screwed up you are, the more opportunities you have to help others. It's simply a question of choosing to pull yourself up by your bootstraps and "get on with it" vs. choosing to sit and wallow in it. Naturally, this will probably happen in an imperfect way even for somebody like G, because it ain't easy.
G would talk about how people loved their suffering exactly because he loved his suffering, and he knew it. But that's already several orders of magnitude more "wise" than your average person!
So sure, he may have been a dingbat about some things, but that doesn't negate his teachings on other things - and it could actually strengthen them.