Rotating pitchers on/off the MLB active roster is going to get more difficult next season, as well. The intent (per the MLB-MLBPA press release) is to increase the minimum time on option to 15 days (from the current 10) for pitchers, presumably as an effort to curtail "roster expansion" moves.
Not clear to me, frankly. If we assume the players who are "assigned to new team/level" are on the appropriate reserve lists, they're not in violation of that part of the rule. There doesn't appear to be anything in the MLB Rules that prohibits "assigning" a player to nowhere. Prior to this season, the Phils always made such "assignments" on paper, but always by adding the player to one of the short-season rosters (typically Williamsport). The folks in Clearwater are apparently telling Jim P. that's what is happening now - but the actual milb.com transaction records do not show these assignments... and at this point, it's not because they're behind in updating - they're changing the player pages to say "assigned to new team/level," rather than assigning the players to any existing roster.
I'm not opposed to what they're doing - just noting that they've taken the charade to a new level this season, beyond what they did in past years.