"And at 300 baud I am sure it was MUCH more reliable and forgiving to some noise on the line."

Absolutely! You'd be amazed to hear some of the recordings we got from a telephone line monitor attached to lines in rural U.S. areas served by so-called "mom-and-pop" exchanges. We also designed a modem/DAA for Australia and were told that there might be kilometer line distances without much in the way of intermediate signal reconditioning. 300 baud can pretty much talk through mud.