Re: And then billed 3 extra hours?
The original Dartmouth time sharing system ran on a GE-225 with a 18 usec cycle time. A GE customer bought this system but found the current release wouldn't run because Dartmouth had upgraded to a GE-235 and the students (of course) used all of the new nifty features of the new machine. So GE sold the customer a GE-235 but put a wait loop in the exec to slow it down to GE-225 speeds. This code was clearly commented. The customer didn't need the extra speed and was quite pleased with the resulting system.
Later I noticed that an IBM 407 accounting machine we use for listing cards would miss every third cycle. I discovered that by pulling out the S2 relay the machine would run full speed. I pointed this out to the customer engineer and he said we were only paying for a 100 line/minute machine and not a 150 line/minute machine so we should leave the relay in. So I did.