Take a look at the pic here. There is no way an architect or the designer (me) could predict, without detailed product knowledge of ICFs, what would happen in this situation. As you can see, the wall run is in even inches, something we always do when designing foundations.
The problem is created more or less by all the ICF block makers, in that their INSIDE corner dimensions are not "modular." In this case with Logix products, the block lengths coming out of the inside corner are either 4-1/4" or 20-1/4", thus the need for a filler block with a nominal 3/4" fractional end.
I think the double cut arrangement, one at 24 and the other at 25-3/4, will work just fine. We'll be sure to scab it all up to reinforce the joints, that, after we glue them all.
The modular dimensions of the woodframed house that sits atop this foundation all revolves around its truss layout and 4x8 sheetply usage, and we are not about to mess ourselves up by fooling with the foundation dimensions just to avoid cut blocks.