Good idea or dumb idea ?

Think about this.........Unless you can put on "NEW" tires ever week this is a must!!!

I even grind new tires because you have no idea how long they have been setting around in a hot warehouse.....after any kind of heat cycle tires will glaze or seal over and they also start producing edges....

until those edges are knocked off that is what you are running on....we used to flip the tires around to make it easier to knock off the leading edge....some of us did, cause of the expense of not being able to afford a new tire....now we grind them and have almost a new tire every week. After you grind one you can "FEEL" the new rubber even if it is a "NEW" tire....EVERY TOURING LATEMODEL RACER HAS A "tire specialist"THAT JUST GRINDS TIRES period!!!

You can't replace a new tire but with grinding them you sure as hell can beat one now days

Not sure what you mean, It's been part of the sport for decades. A tire that gets hot often will smooth off and seal (glaze) the outside of it and therefore not be spongy and gripping on dirt. Grinding a couple thousands off the top of each block will revitalize that stickiness and furthermore regain the groove edges which also dig into the dirt.
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Some teams even put talcum or baby powder into the rubber after doing it. This I am unsure of what it accomplishes.

Worked on LM's in the 80s. We did it weather we thought it needed it or not. If you don't do it, your either gonna throw a new tire on every race or your going to go out there and just spin your tires because they are not going to get the grip they were designed to get.

Setups get you toward the front, Tires win you races. The team with the best Tire Man, Stagger, compound, grooving and siping is going to be on the podium. Grinding is a must if you plan to re-use a tire. You just don't run without doing it. Sometimes you'll see a a guy after the race with a laser thermometer. Or just go and put their hand on both rear tires. The closer you can get both rear tires in temp. The better they'll run as long as they aren't getting too hot.

I figure after first corner ur back down to new rubber. I'm an idiot though.

Depends on the surface. Some tracks just grind off the rubber. Even seen cars come in with cord showing.

Not a idot. Good question. Now you know more about it

I was a tire grunt for a few years. The guys never had me grind a single tire and I don't remember anyone grinding tires in the sprint car pits. Back then if there was crappy dirty job.... I got to do it. Lol

after grinding tire we put baby powder on it to sipe it makes it easier to cut

I know there are a ton of guys "doping " tires in late models . Let's say I've "seen" it done.