The research on which the new extended deep stop is based re-affirms the original 2:1 ratio theory. It indicates that a 2.5 minute deep stop (for their 25m dive) often completely eliminated type 3 and 4 bubbles - bubbles were graded as follows: 0 (none), 0.5 (sporadic), 1(15 bubbles over one minute with bubble showers), 2 (30 bubbles), 2.5 (>30 bubbles with showers), 3 (virtually continuous bubbling), 3.5 (continuous bubbling) and 4 (continuous bubbling with continuous showers). They had some other interesting findings.
Finding one - After a 2.5 min deep stop, decreasing the shallow stop time from five minutes to one minute made no significant difference to bubbling. [more text omitted]
Finding two - Without a deep stop, increasing the shallow stop time did not give you the same effect as a profile with a deep stop. [more text omitted]
Finding three - If a deep stop is used and you stay for less than 2.5 minutes you ACTUALLY INCREASE YOUR BUBBLING as compared to not having the deep stop at all. So basically either do not do the deep stop or do it properly spending at least 2.5 minutes, otherwise you are making it worse.