I'm curios if the Wreck professionals consider a Surface Assistant or they relay completely on them self in the most demanding dives. it is well understands that you need to be self sufficient and carry all your gear with you, but for big dives ( OC ) I guess ( and maybe wrong ) you can carry so much bottles to a point to be unpractical and I believe dangerous to some point.
Of course it is of each individual risk assessment under which risk they determine their dives and are willing to go for that deep and long dive.
What I mean with a Surface Assistant or how I pictured ( never met one nor I know the complete spectrum of their duties ), is a Diver that stays in surface monitors the dive time and have waiting for you at 9m or 6m that extra backup O2 Deco bottle, in that will meet you at the 21m stop to see if everything is alright or assist you if needed, and/or wait for that SMB to come up with a note saying you have problems below, and he will dive down with that extra gas/gear you need to safely return to surface.
Of course it is of each individual risk assessment under which risk they determine their dives and are willing to go for that deep and long dive.
What I mean with a Surface Assistant or how I pictured ( never met one nor I know the complete spectrum of their duties ), is a Diver that stays in surface monitors the dive time and have waiting for you at 9m or 6m that extra backup O2 Deco bottle, in that will meet you at the 21m stop to see if everything is alright or assist you if needed, and/or wait for that SMB to come up with a note saying you have problems below, and he will dive down with that extra gas/gear you need to safely return to surface.