From the highlights we've seen, I get the impression they have been sent down there to stay in game shape and to repeat certain plays from our playbook over and over and over again. Doing this for 2-3 games IMO is effective, and calling them back up for practice with the Rockets is worth it. I've said this before and I'll repeat: I love how we have this seamless relationship with the Vipers where we can maximize development of younger players. We have so many young players at the moment that it's not realistic to assume we can give them all playing time and watch them grow.
I like it. They get to travel with the team, be at games, hang out, practice with the team. Mentally, it keeps them part of the Rockets and still gets them solid playing time.
Under the new CBA, players with less than 3 years experience can be sent to the D-League an unlimited number of times. As for veterans, you need their permission first. http://www.nba.com/dleague/news/nba_cba_boosts_nba_dleague_2011_12_08.html