Trinigordo:My ascents have been done wrong, I have been using the padi 60fpm rule and 3 minute safety stop at 15 feet, and I will now implement a deep stop a la JeffG method which seems to be the better offgassing system.
I don't know so much if I would say that the standard 60fpm/3min@15ft guidelines are "wrong". Define what you mean by "wrong."
For any of my dives deeper than 70ft it is standard practice for my buddy and me to do a deep stop at half the maximum depth for around 5 minutes *in addition* to the standard 3min(in our case preferably 5min)@15ft stop.
I don't think that *any* safety stop can really be seen as "wrong" since it will always help you offgas nitrogen at the ambient pressure of your shallower stop depth after starting your ascent from your max depth. It's just that adding a more conservative deep stop make sense to me and allows me to look at my mug in the mirror and say "I dived a teensy weensy bit safer today", while trying to get all 5 of the swimmers ear drops into my right ear on the first try. Besides I like planning my dives as multilevel dives to build in a deep stop while diving a depth contour and looking for one or two more nudibranchs - I just lurve nudibranchs!