Yeah,
That's because, initially the resistance of the filament is very low, and initially, the batteries can spike a large current in before the internal resitance drags the voltage down. So these together mean for dangerous living when trying to drive a high power lamp to spec or higher with 123's.
I'm sorry, I know that Li chemistry is like the sacred cow of CPF or something, but it is NOT the be all end all of battery chemistries at present. 6 good high current NiMH batteries (or 7) driving the 1274 is a MUCH better choice, because the high current draw doesn't drag the voltage down, and thus your open circuit voltage is much closer to your voltage under load, and thus you can run with a smaller margin.
The best thing, of course, is to use a voltage regulator to run right up to the optimum level of overdrive, and then turn on, open circuit, and hot off the charger voltages are a non-issue.
Anyway, sorry about your 1274. Comes with the territory, I'm afraid.