yes exactly. if i set a high (or actually low in terms on numbers) digging priority for a couple of chunks, all of my miners will run there. i want a method to make sure only one of them does it. currently the only workaround i know is burrows, but that's too cumbersome. assign a worker to do low priority work instead of high priority would be an easy solution, if it was possible.
You've already mentioned it as 'cumbersome', but the burrow method
is very simple (assuming you aren't already doing anything complicated that clashes much with it).
Set the digging/etc as the said low-priority, with high-priority jobs where you the other digger(s) to continue. Sufficiently surround it by a burrow square (or cube, if across levels) and then assign your least/most favoured dwarf to that burrow. When finished, just delete the burrow.
You can finesse this, and may have to in some of the more complex cases, but it
can be as simple as set-dig-rectangle, set-burrow-rectangle, add dwarf, <wait>, remove dwarf.
I admit it
might be nice for you if you could assign dwarves to dig-priority in some sort of thing like the workshop method of restricting workers based on upper/lower skill-ranges, but I suspect that the level of micromanagement won't be less. (If you
keep the dwarf a "5->7 priority" digger, you'd have to go in and set other digging squares to 5-to-7 priorities to keep them busy. Removing the limit, then re-adding the next time, could be more key-intensive than a simple burrow-assignment.)
Maybe wrap-around? Default dwarf aims for 1s, 2s, ... 7s, in that order; But you can set a (different)dwarf to aim for 4s, ... 7s, 1s ... 4s, the first few in the list first, to spread the load? (But don't forget you've done this, then use dig-priorities to 'prevent' cave-ins - the two together thus
creating them...)