Hey Jon,
You got me thinking...what was different between what you did and I've done.
Went back with a brown and a black sharpie and wrote on an arrow finished with minwax w/o oil.
They both wrote just fine ( the black stood out more ) Waited 5 mins and spread some poly on it. Both colors stayed on for the wipe. Wasn't agressive..just a nice "swooosh" with a paper towel wet with poly.
After a few mins the brown was getting faded almost bled out looking. The black was still there..but not as sharp.
I rewiped a couple times with a poly wet pad using more force than I'd ever do for finishing...and both colors wiped off.
I KNEW that the black sharpie wasn't working as well as I'm used to. Went over to my bow finishing section of work..haha...the sharpie I used last time to write on a bow was still there.
THEY MAKE DIFFERENT KINDS!!
The one that works well is Industrial with Super Permanent Ink.
The writing on the pen is red.
Item#13601
Did the above tests with that pen...MUCH better. No "pooling" of ink either at the stops of letters.
The ink didn't rub off until I was seriously trying to rub it off.
Only available in black.
On the pen it says "for indust., lab, and commericial use.
remains permanent under most chemical washes and extreme heat and steam. up to 500˚F"
Hope this helps bud!