Your assessment of it seems correct. I think you could use a 0mm mounting plate and a 4mm DBE because the mounting plates are designated 0,2,4 from a standard height, not that the mounting plate is literally 0mm thick, that would be incredible engineering.
Cheers, glad to see I still have some problem solving faculty intact after 2 months in isolation, though I may have permanent sight damage from squinting at that diagram.
Your assessment of it seems correct. I think you could use a 0mm mounting plate and a 4mm DBE because the mounting plates are designated 0,2,4 from a standard height, not that the mounting plate is literally 0mm thick, that would be incredible engineering.