Steam Pressure (Double Post- Also at Strictly Steam, oops)

Owen

If you are steaming from 1/2# to 2# and occasionally the pressure drops to 0, what exactly happens? Say it goes to 0 while the power head burner purges before re-firing and goes back to 2# within 5 minutes. Is that starting from scratch to make steam? Is it more advantageous to never ley it go to 0 ever while heat is required (they go to 0 at night and only start making steam again in the early AM. They [7 boilers] do run just enough to maintain 180º at night.)

I've been told if it goes to 0 you are making steam that requires the full 970 BTU to begin making steam again. But it requires 970 BTUs per pound of water/steam anyway to maintain steam doesn't it?