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No, I see no value to it for rec diving, other than amusement between dives.
I'm not aquaregia, so forgive the intrusion. When you plan for deco dives it is common to use 2 different SAC rates:
1. Working SAC rate -- for the non-deco portion of the dive when you might be swimming or moving around with a regular degree of physical activity
2. Deco SAC rate -- for the deco portion when you are not supposed to be doing a lot of physical activity. You are supposed to stay mostly idle while offgasing.
Logically, your working sac rate will be greater than the deco sac rate.
Just out of interest aquaregia what do you mean by "working SAC"? Is that your SAC while swimming or something more strenuous than that?
There are two ways, one of them more accurate than the other. The first is to note the time and pressure at two points while you are at roughly the same depth during the dive, and do the calculations from there. The second is to use the average depth of the dive and the total gas consumption and dive time.
One would think, for heavily multileveled profiles, that the latter would be rather inaccurate, but I have to say that I have calculated my consumption for square profile dives and multileveled dives, and it comes out pretty much the same (within the variation it has from dive to dive, anyway).
Using the average depth is the proper calculation, not just an approximation, so you shouldn't have any reservations about calculating over the entire dive, using the average depth, whether square profile or multilevel. Since measuring the presssure difference over just a 10 or 20 minute period is likely to have errors, I actually prefer measuring over an entire dive.There are two ways, one of them more accurate than the other. The first is to note the time and pressure at two points while you are at roughly the same depth during the dive, and do the calculations from there. The second is to use the average depth of the dive and the total gas consumption and dive time.
One would think, for heavily multileveled profiles, that the latter would be rather inaccurate,.......