Wait for the cymbal to sound. A script will add the current timer to the timers list, then send a broadcast that does it again, and so on. The broadcasts -do- have a tick delay, but in the absence of any screen updates Scratch runs them as fast as possible, in a sort of 'automatic Turbo mode'.
I thought each broadcast would have a frame delay before the next script runs, but I was mistaken. In Scratch 1.4, the same setup results in times that are separated by ~0.03 (1 frame). The ST must have changed something :) I did the same experiment with a tail-recursive broadcast and, after the first two timers are added, they're separated by ~0.03 again. Likely this is to prevent an infinite loop.
