Disproven? Please cite any recent study that did this because I'm not aware of any. Please don't cite the NEDU study because the criteria used for deep stops did not come close to the parameters VPM uses.
To turn it over, is there anyone reputable today actually advocating for a bubble model algorithm?
When the deep stop theories first came out, nearly everyone jumped on that bandwagon, accepting it as if it were a proven idea rather than really just an hypothesis. When studies finally started to be done,
none of them supported the use of deep stops.
The commonly used VPM conservative factors are close to Buhlmann with GFs of 20/80. RGBM and the "Pyle Stops" methodology are roughly the same. As stated above, no research supports making decompression stops that deep, and every expert I know of advocates shallower first stops.
Mark Powell was a devotee of VPM and deep stops, and when TDI (his agency) redid their decompression procedures course a few years ago, when I was still a TDI instructor, they went all in on deep stops and VPM specifically, using material from Powell's book
Deco for Divers. Powell moved away from that a few years ago, saying some stops are too deep. He recently performed a study of his own, although it did not rise to criteria needed for publication. In it, he did something that to my knowledge had not been done in previous research. He not only checked for bubbling right after divers surfaced, he tested them repeatedly afterward. The difference was significant. The divers who used a shallower stop model had bubble levels drop off over time as predicted, but the deeper stop divers not only maintained high levels much longer, they initially
increased over the initial readings after surfacing.
This article summarizes this, but it was published before Powell's recent work.
