Been there and I can appreciate not only the skill set, but also the tranquility. My last solo dive was a 135 minutes with a 10 minute deco obligation and I came up 5 minutes later than I planned. I was at 1050 psi and my target was 1000 or above. It was a wonderful dive despite my DIR buddies thinking I was going to commit suicide as I had recently told them I was getting divorced...
Not directed at you Mdb:
What I don't like is entering the water with someone who in the pre dive plan makes it sound like they will be my buddy only to find out that do to some whim unbeknownst to me they take off during the dive. I'd rather have it up front that we are solo diving or we are team diving not "lets see what happens diving". One could extrapolate and say the dive plan was to only go to 100' for 10 minutes on air, staying in NDL, then we work our way back and stay together as a buddy team. Mid dive I say what the heck I just sort of feel like going to 200' for a few minutes an incur a deco obligation. See you back at the boat. Sorry, but that wasn't the plan that we talked about and it blew all the parameters of said plan completely away.
I understand flexibility within the plan, but blatant irresponsibility is uncalled for and not allowed in the style of diving I choose to do.