I'm still too scared to try it, even on my pretty much worthless test bass!
I can't get the neck to be anything like the same shape when it's without tension vs with string tension.
Plus, when it is under string tension, the slightest tweaks on the TR can make the highest frets appear in different places on the neck!
It looks easy on video clips, but I reckon there's a good chance of a DIY job making things worse rather that better.
And once you've taken fret material away - you can't put it back! ๐ฌ