I had smirked at the notion that some Sharpie ink would cause out-of-whack spins but, in the last year, I had a completely different experience with several Pioneer DVR 118s.
Somehow, they allowed a mis-aligned DVD to start spinning at 'full speed' and those exploded in the drives. Hundreds of shards and pieces, flakes, everything.
You've seen a DVD that's been snapped in two. Maybe in 4 or 5 pieces. Maybe you've seen one smashed on the street. But they were nothing like these 118s' obliteration.
I mean hundreds of tiny flecks and shards, pin-sized spikes, all thru the unit. There's be a 'sheet' of some material that might be fingernail sized, but everything else was closer to sand-pellets.
When it happened on one, I just wrote it off as a queer unit. On the second one, I was thinking, "Did I do something wrong? I've loaded tens of thousands of disks, but NOW I don't know how?!!" When the third unit blew up a disk, well, that was it. Three out of 10 or 20, whatever that order was. We started pulling them out and 'saving' them in a dust-collector corner.
The strange notion was the incredible RPMs that disks must attain. How else could those pieces be so thoroughly obliterated? I mean, porcelain blades on a power-saw don't shatter in so many pieces!
With that in mind, maybe in fact a TINY shred of Sharpie ink would create some off-balance during that high speed spinning. (Of course, probably McLaren engines would, too. REDLINE!! REDLINE!!! I can hear Cholla muttering, "She ain't learning to double-clutch on MY rigs!")