Much is reported online about initial rotovation, with or without Roundup. In my opinion the actual problems are understated. and can be disheartening 6 or 7 weeks down the line. Rotovating might well be a good thing on a weed free constantly worked plot, but not a neglected one. The only good that comes from an initial rotovate it is that it breaks up the soil to physically help the hard work of the next unavoidable stage of careful methodical hand digging that is necessary.
As for the burning or disposing of the collected couch/bindweed etc roots, I'm not so sure. I have found quite the opposite. Not through any prior knowledge, but just laziness, tiredness, and a shortage of time and space on my initial dig left me with a large area that accommodated all the root pulling from the rest of the plot.... huge amounts of bindweed, couch and dock. After covering it all for 18 months, I then uncovered and just pulled anything that came to the surface just like one would anywhere.
A further 18 months on, I have just dug that area like the rest of the plot and planted sweet corn. I have to say the soil there is now THE most fertile and fibrous of the whole plot, it's real alive healthy soil. Such big volumes of rotting down plant root and material is hard to come by. And it is requiring virtually no weeding compared to elsewhere. I'm not saying put this couch etc in a bin, but I am saying save it, cover it and rot it down, and in 2 years time you'll have a great deal of very useful growing medium indeed... it will rot down eventually if you don't allow it sunlight. Yes, there will be the odd bit of root surviving ready to populate, but no different to anywhere else on the plot.