Take listerene and some vodka(or any 40% alcohol liquid) mix them together. Then apply it using a paper towel to the rim. Let it dry for 2mins. Works for like 3~4hrs which is better than tar plus also keeps the wheel clean. I use a bombshell painted rim and spanish fly pads and a V brake. The results are always amazing... mmm vodka...
smirnoff vodka is poo and I don't feel bad about wasting it. Now Stoli, Stoli gold, or Grey Goose would be a different issue. Then I would have to slap myself... As far as grinding goes. I am not a big fan of it mainly because you can grind the rim only so much and it chews up the pads quicker.
If you want good braking, there is NOTHING but a grind. Holds in the wet, holds in mud, holds in everything but an iced up rim.
Show me one person who's grinded a rim so far down that theres nothing left. I've gone over a year on a rim, with constant grinds, with little effect to the width of the sidewalls...the pad issue- depends on the rim. On my monty mod rim I went through pads in like 2 months. On a dx 32 I had the same pads for over a year, and they hadn't gone down at all. Monty rims are super soft, dx are pretty hard.
I grind like once every couple months and you can get a really good grind on one wheel in less than 10 minutes as long as you use the right disk. Plazmatic pads work great, but I tried Graham Wilhelm's koxx bloxx and I've ordered a pair They are going to be AMAZING!