Thanks for the link. Looks dangerous, sounds very noisy. I'll just work on zone 2 alignments a little more instead. Safety first.
I don't think its that dangerous. Not much more dangerous or nosier than say using a Speed Stik or swinging a club.
When I was down at the Swamp, Yoda showed me how to use the the Speed Chain and it does teach you a lot. For example I have a habit of dragging the club way inside on the backswing but do that with the chain and you end up hitting youself with it and on the way through you can't whip it too much from the inside either as again you will end up hitting yourself.
For me it taught me how to really use my pivot (for a swinger the pivot is where all the power comes from) and I could really feel that I could trace that planeline really well. On the way through impact and to follow through I could really feel that I was 'dragging a wet mop' and I could sense the lag pressure in my number 3 pressure point.
Alex
What are the merits of this training aid over the speedstik?
Not to mention the swing mechanics benefits, but from a pure speed standpoint:
The speedstick, momentus, and weighted clubs are isotonic or "dead weight" devices. Meaning when one swings them, on the downswing their own inertia plus gravity is assisting on the downswing. They are probably ok for strength but not real effective for speed IMO. They also fail to meet the 4 laws of specificity for speed training.
Contrast those with the SC. The SC is a variable weight resistance device which provides an overload/resistance on the crucial start of the downswing and thru the impact zone. And it can be swung extremely fast. Much faster than weighted clubs and the speedstick. It is the only training device I know of that meets the 4 laws of specificity for speed training.