[TELECOM Digest Editor's Note: Plus which, on (at least the older) AE
> rotary dial phones, the dial would return 'faster' when you removed
> your finger. WE dials pulsed and clicked their way back. PAT]
The dial speed is about 10 pulses per second. (A good modem manual will tell you exactly the "contact make/break" times and the settings for outside the U.S. as well).
Anyway, I believe panel switching and certainly crossbar and ESS could and would accept 20 pulses per second. Way back in HS a kid figured out on his phone dial an adjustment to make it 20 p/s and it worked (on either #1 xbar or panel). PBX switchboards had 20 p/s dials.
However, I think they realized this higher speed was rough on equipment and did not provide it to the general public for that reason. I don't know if SxS could handle it but SxS components had wear issues and certain improvements was rough on SxS unless it was carefully spread out among switches within an office.
During the early ESS trials at Morris IL subscribers were given high speed dials (and also tone ringers). I wonder how subscribers felt after the trial was over and they went back to their old system -- and had to wait 25 years until such features were available again.
Several years ago the Wall Street Journal reported that a good number of phone customers still had rotary service. I suspect that percentage has dropped; I wonder how many people still have only rotary phones in their home today.
As discussed, some pay phones were intentionally converted back to rotary to avoid drug trafficking, but with cell phones that's not an issue anymore.