Grolubao Yes! AT was one of the best things I ever got into. Had a great teacher in Boston who worked with me while playing, and sometimes when I couldn't get my drums to his studio I just imagined playing and it had a great effect then, too! Alexander Technique is awesome. Any particularly describable things you can share from AT that helped you out?
MrInsanePolack, Before I say anything I should probably tell you to inform your doctor you intend to stretch. I think that's good legally in case you get hit by lightning while stretching on your couch. I would do Kelly Starrett's super couch mobilization. Here's a decent video to get the idea.
http://www.youtube.com/watch?v=tweCntuDdVY You can do this with your back leg against a wall, ankle against a padded chair, or with the knee on a couch seat and the front leg on a coffee table or nearly straight out on the floor in front of the couch (my preference so I can distract myself with a little TV.) He has actually made some errors to ease up the stretch. You want your back shin as close to vertical as possible, and you want that thigh vertical and under your body. You can see in the video he has angled his back thigh out a little to relieve the pain of really stretching it. That's because he wants to look good for the video with his chest up. You want your spine to remain "straight" (there will be natural curves, but you know...) If the stretch is too deep, you'll probably have your torso nearly horizontal to the floor. That's fine! Just keep the position of your legs correct. Back leg as I described, and front leg as if you were squatting. Hold for about 2 mins each side if you can, slowly moving in and out of the really painful spots. Don't make a face! Stay relaxed. If you can't be relaxed, bring your torso down (spine and neck aligned) to ease it up. If that stretch is too tough on your knees let me know and I'll look in my books for some scaled down options.
Check out this video as well, from Mr. Starrett himself:
http://www.youtube.com/watch?v=JslrFB06wPU
This explains a couple things. #1, since you probably never bring your knees above your hips apart from drumming, you don't have range of motion. When you play double kick, you're using your chronically tight psoas for stability, and then doing fast powerful actions with you legs at the absolute end range of their mobility! Makes sense you might hurt. Try practicing getting into a full squat as he shows, with knees out for stability rather than relying on your overworked psoas. This will show you if you have limited range of motion for your hips that may be forcing your hip flexors to work against restrictions in the joint instead of just lifting up your leg. Squatting like that may be tough on your knees. If so, don't do it, and try imitating the position with your back on the floor, feet on a wall, and slide your butt as close to the wall as possible. Feet pointed straight, and knees outside your feet! Without knowing what happened and how bad it was, you may not be able to do this at all, but I'd bet there's a lot of potential for increased motion in that ACL area. I can't advise on that without seeing it though, so unless you live near NYC or want to try a skype appointment, I'd leave it, or see someone near you who can help.
Dre25, That's good that you can control it! You have the choice now to hunch or not. Hearing better maybe isn't so crazy actually. My dad is a psychologist and he can often tell what I'm thinking or about to play based on which ear is pointed where in an improvising situation. I don't get it, but maybe there's something to it. If it works, just don't hunch any other time, and drumming that way shouldn't do too much damage unless you really hold it tight. Might affect playing ability though...but sounds like you're taking care of that shoulder the right way!
As for pain, I just say that pain is not an indicator of something being wrong. It's a result. If you start hunching your shoulder, that's "wrong," but while playing you probably don't notice until it starts to hurt, right? That's the result of the poor posture. So if you feel pain it means you've already done damage, and should stop for the day if you can, because your musculature and nervous system are probably tired and stressed out. Following that thought, be careful with thinking that playing for 5 minutes and not hurting means you've been training yourself into better technique. If you're doing the same thing that would make you hurt after 15 minutes, you're still training that poor technique, and just stopping before the pain point. If you would only hurt after an hour, that may mean it's poor technique, or it may mean some muscle groups are weak and get too fatigued to help you do the correct technique you had earlier in your practice session, and in that case, shorter practices are exactly what you should be doing. It's just hard to know which is which sometimes, even for myself, so I err on the side of trying new things and seeing if I can find something that just feels good and has no potential for pain.
Finally, and it's probably not really the best thing to do, but I always tell people to respect their bodies and only do best practices during practice, but that if you finish a gig hurting and smiling, then that was probably the right thing to do. Keep working in the practice room, but if you enjoy gigging and jamming with people more than you dislike the pain, just play and have fun! Serious pain like tearing an ACL or wearing down your rotator cuff will probably make you not want to play. Gigging also makes it easier for me to be very deliberate and ONLY practice EXACTLY the technique I want to use, because I'm not starved for playing time. To hit Vince Lombardi's quote "Practice does not make perfect, practice makes permanent. Only perfect practice makes perfect." But playing is fun! So play if the pain doesn't stop you, and do perfect practice whenever you can, cause that's fun too!