Confirmed: The game does not behave the same if you choose 1 day+ increments than if you choose 8 hour- increments. In the former case, sub-increment number is drastically reduced, sensing and opportunities to react happen only on rare occasions, and the game runs faster. In the latter case, sub-increment are respected, sensing and other combat-relevant events happen more often, and the game runs (quite a bit) slower.
I'm giving serious consideration to using the text above as my post tag because this feature trips up *every new player to the game, and quite a few veterans*.
This feature has not changed in essence in the transition to C# Aurora, and continues to be a critical part of Steve's toolkit for delivering an acceptably responsive game.
That said, I do have some major issues with how the game continues to fall down on managing automatic transitions between the two and consider them among the most vexing, systemic problems with the Aurora game engine. Forgive my heat, fellow players, but losing entire fleets to the game effectively turning off my sensors when I hit a button right next to the save game button ... is worth getting a tad perturbed about.