Looks as if doc is gearing up for the playoffs in an intelligent way. Reducing the number of plays will help the new players, of which there are many. Fewer plays to master, more reps on the plays they know.
As for the starters, they know the plays but can now focus on executing certain plays better.
Honestly, I thought it has been the celtics offense that has faltered as of late. Hopefully this will keep them focused and allow them to all execute plays better.
It is not that 1/2 the plays have been bad all year. Over a season, doc puts in lots of plays to provide variety, test new ideas, etc. Some work, some don't, some are better than others for certain players.
By now, Doc knows which plays work with which player combinations and will focus on those plays that work the best.
Good for doc.