Same if I was on nitrox and other diver on air. Why should I limit my bottom time by diving with someone when I paid a premium to have a longer NDL time ?
So what you're saying is, Land Fish's boat crew were complete morons, they paired a couple of computer-less newbies with seasoned pros who were happy to let them tag along while diving nitrox twins to a hundred metres, in a fog, inside a cave and uphill both ways? And you know that because you were there, and you didn't scream at them YOUR GONNA DIE!!!!?
Dive computers were our second gear purchase ever. I don't wear mine to the pool. I do wear my casio but only because I want to be out and packing before the lifeguards start turning off the lights and licking the doors. Edit: that was supposed to be locked of course but I'm leaving it as is.