From a savings "High Score" perspective, 3 meals per day will net you that "High Score," however, it doesn't work out too well for reality.
Over the past 3 trips, I typically did either a 1 TS breakfast or lunch coupled with a signature dinner. Due to the way the plan works, the per credit cost is far lower than the TS credit cost on normal
DDP, plus you get more for that credit than you would on the DDP. This shift downward in cost but upward in value pushes the signatures into cost effective range when working with credits.
So, for example, using the 2013 prices, we've figured out that a DDP TS credit "costs" roughly $36.60, while a DxDDP credit costs roughly $31.32 (credit for the formula to figure this out goes to Faldred in
this post). So, 2 DDP TS credits costs you about $72, while 2 DxDDP credits costs you roughly $63. Spending $72 on entree, dessert, and drink can be tricky, if not impossible. This is what drives the value of 2 TS meals down on DDP. Conversely, spending $63 on an appetizer, entree, dessert, and drink at a signature is entirely possible. While you'd still likely get better savings from 2 separate non-character breakfast meals, you'll still be fine at the signatures. (It
is a lot tougher for 2013, for 2012 the per credit cost on DxDDP was ~$27, making $54 the mark to hit at 2TS. This was quite easy to do. Now, it'll take a little work.)