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i.e. You boys better watch yourselves 'fore you get this thread thrown into lockdown.But this is a different discussion. OP asked why no doubles at Ginnie... answers were given.
Safety is not inherent in any configuration, nor any amount of gas, but in your ability to use it effectively.
Intro divers in doubles have a worse safety record than intro divers in single tanks. The whys are debatable.
It'd be nice to know how many accidents were avoided due to the additional reserved provided by doubles.