The club releases as an effect of what the golfer is doing.
If a golfer does the correct things then the proper release will happen.
Nobody who plays good golf tries to time the release on all of their shots.
It's mechanics, pure and simple. Most of them are not 240 pounds, not at all. I'm 6' 2", 195 pounds and I'm still average/thin build. If they were 45 more pounds with 2 less inches less height, they'd be fat.
Swinging hard doesn't mean the ball with go far. It's all about making the proper movements. I don't feel like I swing any harder today than I did 5 years ago, but guess what, I carry the ball 50 yards further.
At least 50 guys on the PGA Tour never carried a ball 300 yards in 2013 during competition. I won't believe they never once gave it their 100% swing. http://www.pgatour.com/stats/stat.02409.2013.html I'm skeptical of this 80% talk that is thrown around too, even though they say it.