I just got caught up with last week's Midweek Motorsports show on which there was lengthy discussion on the draft TUSC rules and the challenges to both the organizers and the teams of reconciling the performance gap between the Daytona Prototypes and ALMS LMP2 and the uncertainties that the teams have in their choice of car for 2014. The commentators presented this situation as the only alternative to just taking 2014 off for the series to do testing and returning in 2015 with obvious negative consequences of shutting down the series for a year.
I think there is another alternative that may have been discussed in the past but could still allow teams and organizers to test and learn while racing in 2014 while not getting stuck with racing a chassis that will never be able to win a race: keep LMP2 and DP as separate categories for 2014 with an aim to merge them (or do something entirely different) in 2015. LMP2 would remain ACO compliant and teams that have these chassis already, could continue to run them. The current DP teams would incorporate many of the new rules to improve performance, but would remain as a separate class. This would allow real world testing of the rule changes, while not forcing the current DP teams to either switch to LMP2 or compete against LMP2 with a slower car, at least for a season. Then, in 2015 everyone--organizers and teams--can make a more informed decision about the best way forward for LMP2 and DP.
It seems to me that, either way, DP will be phased out over the next few years, unless there is a separate class or series created for it because a DP just isn't an LMP2.