Tritium sights on a pistol while shooting under NODs are at best a distraction. That being said, a couple of NV classes back we had a guy from VA that had a Beretta 92 with only tritium sights and he seemed to make it work fine with a PVS14 for the pistol portion of class.
I would say definitely don't change your NODs focus, just superimpose the sights on the target, it's not like you need a crisp view of the glowing tritium to shoot.
I run dual illuminated RMRs on pistols and have never had issues, never "too bright" or anything like that.