On this project it is my opinion that units crunched belong to the cruncher. If the cruncher chooses a different team then the new team gets the benefit when the new member joins.
The way Howard and Company has set up the point system on this project is very similar to the scoring system used at SetiAtHome, the grandfather of Distributed Computing projects.
Of course, my opinion on the Genome@Home project is that when you crunch units for a team, those units should stay with that team.
The scoring mechanisms were decided for the various projects before the first team was created. I am not in favor of changing the rules after the fact.