Well, I'm no technique master and certainly not qualified to teach anyone such things...and like Phil said - you're going to want someone watching you, analyzing your movements, and correcting you.
That being said, I've been seeing the same drum teacher for appx. 3 yrs. He's been playing for almost 40 years and he has beautiful technique. There are certain things he just could not spot that I now realize I was doing wrong. The biggest one being tension.
It's easy for someone to say "keep your fingers on the stick and use the fulcrum - but not too tight". Yeah...sure...I'll do that! Ha! How it feels when YOU play is something no one else can fully analyze.
I found that I would start out doing great....but start to slouch after a couple of hours of steady playing....mistake one. I also found that as I would slouch, I would grip harder and differently, adjusting to my poor posture. My strokes would change and it was overall, poor technique. I didn't warm up enough in my first year of playing...most times I'd just sit down and do my thing...big mistake number two.
So, after three years of daily practice I can only say that I've *begun* to scratch the surface of what proper technique is, and I learn more everyday. I've got a long, long way to go....BUT....I'm now able to play as long as I want, as hard as I want, and am a much better drummer *overall* because of the little adjustments I made over the last two years, since the injury.
The biggest things that I remain conscious of, outside of grip, stroke, or anything related to the sticks:
1. Sit up straight
2. Relax
3. Breathe
They're easy things to say but IMO, they're the hardest parts of learning how to be a drummer. It's very easy to forget and to slouch, tense-up, and hold your breath. It's almost another level of independence...remaining aware of these things while playing.
As far as grip, I just had to learn to use my fingers and allow the stick to do the work that I was forcing my wrists and arms to do. Once I developed a better free stroke and learned how to use my fingers in relation to my fulcrum...I was able to get much more mileage out of my arms.
Of course there are other micro-adjustments to obsess over - everything from the angle you strike the head to keeping your shoulders squared...or whether to use the first knuckle of the middle finger...or somewhere in between the first and second...and so on.
I'm a programmer by day...so I use a keyboard and mouse for 8-10 hrs. everyday. I practice every night for about 2 hrs. and play w/ the band for 3 hrs. once or twice a week. You're also going to have to learn perfect posture and *keyboard* technique while you're in front of a PC...if you want to do both.
One more thing I'd like to mention, is physical therapy. If you've already got an RSI and you're in pain - nothing is better than a procedure called ASTYM, in my opinion. Google it, ask your doctor about it...it's nothing short of a miracle. It's also something you can easily learn to do yourself at home and it poses no physical danger. It's based on the ancient eastern practice of Gua Sha. Cortisone, ice, anti-inflammatories, surgery...it's all ineffective and unnecessary for most people. I AM NOT a doctor...this is just my experience and opinion.
Sorry this got a little long-winded, hopefully it was helpful in some way.