WOW that is an awesome write up. It might sound arrogant, but so much of what you "learned" are lessons I was taught over 40 years ago. We used to night dive the Point Pleasant inlet a lot, but then a guy got lost and came up under a boat and he was killed - then my dad said no more diving there.. so we talked him into taking us to the Shark River Inlet for night dives. My buddy and I were teenagers - too young to drive yet. Dad was not a diver, so he thought it was better.
I remember one rough night dive, I think we bailed early on the dive and decided to walk out on the jetty (pt pleasant manasquan inlet. We found a diver "some old guy" probably 45 or something.. and he was wearing a unisuit dry suit which required like 45 lbs of lead and he was trying to get out on the rocks and was getting bashed on the rocks. Too much weight, too slippery, too rough, too weak etc. We climbed down and physically hauled his butt up on the rocks. i remember it as dangerous and difficult for us and we had 2 or 3 of us to assist one guy. He might have been killed. He was very appreciative and I think he said he was trying out a new dry suit as well.
Ever since then, the hinderance of heavy lead belt, inability to swim well in a dry suit, strong currents, cold water, wave action are all things I carefully consider. It sounds like you totally screwed up navigation, made assumptions about the jetty (which you probably could have researched before the dive) and generally took on a dive that was much too adventurous for you and the conditions. 6 inches of visibility... I would not be diving in swells and surge in that..If you decided to dive in such poor visibility, then you should have just gone down, swim 50 feet and come back 50 feet... not trying to do a whole jetty you never had seen and had no intel on.. Way, way too aggressive in my book.
I think that was a big error on your part. Another thing that really worries me about a solo dive like that in ice cold water.. what if you lost a fin, got a cramp or were later in the tidal cycle? You would have been swept out to sea. I assume you had nobody on shore or any contingent plan for this scenario? In the summer you might get run over by a boat.. but somebody would probably pluck you out of the water.. but in the winter, I would think you might die of exposure.. drifting off the inlet with no way to get back.
Your comments about failing to walk around the full jetty and do useful recon. before the dive was also very important. This is something I will generally do - say when diving a jetty, or shore diving in Maine or something. You really got to take the time to get down to the water, watch for the wave sets, look for hazards and exits etc. If I were doubtful, I would often snorkel the site first. I can scramble up rocks without a tank on, much, easier and safer. If it seems cool snorkeling, then I can go back and get the tank.
The part about the BC inflator has me totally baffled. You have an inline shut off valve for the inflator??? If the inflator is free-flowing and inflating (and you decide to dive anyway) why not just unhook the hose and orally inflate?? Even with the hose shut off and connected, you can orally inflate the BC .. right? Solo diving, in super cold water and knowing the power inflator function is not there... should have reminded you well before the dive that you are going to be orally inflating.... Am I confused.
I am confused why you did not remove your tank, fix the cam band, put the tank back on and continue the dive? The ability to do that is absolutely ESSENTIAL (solo diving skill) in my book, especially when carrying you own entanglement hazard (the flag) - not to mention all the power pro line on the jetty...
In any regard, I've had my share of "dives I won't repeat" and many lessons learned... It sounds like you made it back based on a little luck and a good degree of physical strength. A simple slip on those rocks and banged head could have been fatal. It's quite a feeling walking back from a dive and knowing you muscled your way out of a bad situation.