As a back-up to using a computer and/or using tables while planning a dive does considering average depth work as well?
For example if while diving I figure that my average depth has been around 60 fsw and I've been down for less than 60 minutes then I should know that I haven't exceeded the NDL for the dive as a whole. Correct?
I could have exceeded 40 minutes at 70 fsw but if I balanced out the dive at 20 fsw for 19 minutes then for the dive as a whole I've met any obligations and could do a free ascent?
I'm just asking if using average depths on the fly while diving is a useful way to double check the computer or to dive without a computer just using a timer and depth gauge plus having knowledge of the tables in your head.
For example if while diving I figure that my average depth has been around 60 fsw and I've been down for less than 60 minutes then I should know that I haven't exceeded the NDL for the dive as a whole. Correct?
I could have exceeded 40 minutes at 70 fsw but if I balanced out the dive at 20 fsw for 19 minutes then for the dive as a whole I've met any obligations and could do a free ascent?
I'm just asking if using average depths on the fly while diving is a useful way to double check the computer or to dive without a computer just using a timer and depth gauge plus having knowledge of the tables in your head.