One thing I missed in my Alpha-Fragmentation calculation was the daily mineral exploitation missions.
The experience I have had is as follows:
Fit up Termis MK II with Geo-scanner and miner modules, Spice to Taste, get daily assignment, undock and directional scan for nearest daily mineral.
Find mineral, tile scan, and mine.
The daily, at least the Tellesis one, requires a low amount of rare material, and with the reduction in fluffyness, I can get complete the mission without needing a can.
A couple caveats then, the Termis has a good Geo-accuracy bonus and I'm using a T4 scanner (I have max geo skill from artifact hunting, but it's not a requirement); but even with a T1 scanner with skills you can get a fairly good scan.
While I'll probably only be doing those missions for another couple days, to get rep up, there should be a whole new batch of miners on A1 and A2 islands that will want to use the closest tiles for the missions, and can still get value from a couple of green tiles.
I haven't looked at the lvl 1,2,3 mineral exploit missions, but if they require 4,8, and 12 rare ions (respectively) to complete, then this can also be done in arkhe's, argano's and termis's very easily without needing to can mine.
Fragmentation is still going to occur on the fields that end up far away from the terminals, especially true for A2 islands. If fragmenation is allowed to continue unchecked for months and months, there will be hundreds of small patches of tiles around the perimiter of the islands; which won't interfere with directional scanning, but would 'lockup' a significant amount of the 'minimum' resource calculation.
I don't think the purpose of this mineral mechanic should be to force a subset of 'do-good' players to run around cleaning up tiles. The mechanic does an excellent job of getting players to be more pro-active in searching for ore, which is good.
I would say, Monitor the fragmentation, and if it becomes an issue where the 'ore-bunnies' pile up in the corners (even if it takes months to happen), implement something to counter that.