That shouldn't make a difference...
NEW Macs? OLD Macs?
Does it actually take 74 minutes to write a 74 minute CD?
I've seen a program or two that will *show* 1x (WaveLab if I'm not mistaken, is one on a PC) but it will burn at the slowest speed the drive is capable of (4x in this case).
Otherwise, you really don't want to be burning at 1x anyway unless you're using a 4x (max) drive. In any case, I'm not saying "it doesn't" -- I'm just saying (A) it would surprise me to no end if it were true and (B) I most certainly wouldn't suggest it. 1x was great on 2x (and 4x) drives. After that, there's (IME, and countless others) a "sweet spot" at around 25% of a drive's rated speed.