Add in the time to clamp and unclamp... =)
With a cordless dremel, I can take it anywhere with me..... It may need a battery, but I don't have to be physically at the truck either.
In fact, I can touch it up quickly while up in a large tree... done that with your clamp and file?
No bother with lowering it down, letting someone else do it, etc etc... just a min and a half and its good to go again.
Where do you put your dremel you say? In the left cargo pocket on my BDU's... weighs less than half a pound. Barely notice it. I only take it up for larger stuff though. It's not a regular thing.