Anyone believing that this dispute is political, no matter what the President of the RMT may or may not have said, is deluding themselves. This dispute is primarily about safety, and even Southern's attempts at manipulating public opinion by taking out full-page press advertisements in order to try and reduce the dispute to prosaic levels does not disguise this fact.
But keeping to the thrust of this topic...
You cannot really compare the agreements of the past with the issues of today. Yes ASLEF did eventually cave in and allow DOO when BR waved a big enough carrot under it's nose, but at that time DOO was being sold on the basis of the safeguards provided by the door interlock circuit. The thinking back in the early 1980s, a time where there were few if any 12 car trains, was that if you got door interlock you were safe to depart, therefore you didn't really need to worry too much about checking back along the train.
But times have moved on. Since those times the safety culture on the railway has burgeoned and emphasis has been placed more and more on operational incidents and how to reduce them. From the 1990s onwards this was all focused on SPADs leading to the introduction of TPWS and OTMR, amongst other mitigations. In more recent times the focus has shifted to the "Platform/Train Interface". Several incidents have highlighted the weakness of BR's original confidence in the traction interlock circuit. More scrutiny has been placed on safe despatch and watching trains clear of the platform to ensure no-one is at risk from injury or death.
And this is where all the arguments in favour of DOO fall down. Where is it you expect a driver to be looking? While CCTV DOO despatch might be the best option from the many alternatives available, the fact of the matter remains that a driver cannot (and should not) be expected to have to juggle so many different tasks at the same time. While the Electrostar fleet switch off the CCTV system at speeds about 10mph(?), I have it on good authority that the system used on the Hitachi IEP fleet will remain live until the train has cleared the platform end. At complex locations such as London termini and other major stations such as Bristol Temple Meads a driver will have his/her hands full with controlling the train speed and observing the signalling. Watching the monitors to ensure that no-one has fallen under the train as it pulls out (it has happened on several occasions) at the same time is simply asking for trouble. Any driver unlucky enough to be caught speeding, committing a SPAD in the station throat or suffering a "one under" while pulling out is going to be in for an uncomfortable time. Therefore drivers are obviously and justifiably concerned about the introduction of DOO. This isn't just a reductive hankering after archaic and outmoded working practices. This is an attempt to bring DOO into a very different set of circumstances to those in existence 30 years ago when it was first introduced; circumstances that do not really bare comparison. I should perhaps also note at this point that there have been no other attempts at comparable large-scale introductions of DOO in the last 3 decades.
But to answer your point directly, as an ASLEF member I can categorically tell you that no amount of money would secure my agreement to any extension of DOO operation. Safety is not something that the industry should be able to buy, and that's a message I'm taking to all the other ASLEF members I meet. I've worked DOO in the past and I can tell you that I'm glad I don't do it any more. Looking back I can identify times when I could very easily have suffered a career-ending incident and only failed to do so because of luck.
As for what else I think about DOO, well my thoughts are already a matter of record. You can go back through the search facility and read what I think if you so wish.