Original Apple IIc serial inaccuracy (?)

[schmidtd <schmidtd@my-deja.com>]

So, my $12.01 IIc arrived a couple of days ago.  It turned out to be
an original ROM 255 model, with the 74LS161 chip instead of the
oscillator.  So, it should have the 3% timing deficiency with its
serial ports.  (ref: http://en.wikipedia.org/wiki/Apple_IIc#Serial_port_timing_fix)

Strangely enough, trying out ADTPro with it on both Windows and OSX,
this little IIc was able to transfer disks back and forth flawlessly
all the way up to 115.2kbps.  Have computers become more tolerant of
timing inaccuracies over time?  Or was the problem only with more
hardware-ish devices like modems and printers?