My two weekly sessions are normally spread a couple of days apart, but have been on consecutive days several times because of scheduling conflicts. It definitely feels different than having a more evenly spaced schedule, but I've still found it helpful--my experience is that it makes the two sessions feel almost like one long session. And I think with any consistent therapy schedule (or any other schedule), it probably takes on a different character once you adjust to the consistent rhythm of it, and becomes helpful (and difficult) in different ways.

My inclination would be to try it and see how it goes, but I can see why you're concerned about what it will be like.