I know how he feels, kind of. I had to WD from The Heritage qualifier two years ago because I was hitting balls with a weighted club (that you are not supposed to hit with) and ended up with tendonitis in my left wrist which caused me to flinch at impact. Irons were okay (at least could limp them around) but the flinch caused an extreme fade/borderline slice. For me getting into The Heritage is the equivalent of Goosen playing in a major. Actually, me getting into The Heritage would leave me walking on air and for Goosen, The PGA is "just another" major in his successful career. I hope he heals quickly and hasn't done any major damage.
How'd ya guess. Both VJ and Tiger were doing it at the time but what wasn't published was that instead of the unforgiving steel rod for a shaft, they were using a similarly weighted club with some shock absorption. The only thing I hit with the momentus now is occasional chip shots...this is an amazing tool to feel the proper stroke for a chip shot.
I like to swing it SLOWLY, focusing on controlling the club and tempo 5-6 repetitions between club changes when practicing. Helps me to stay with a nice smooth swing.