Juco, as the others said the video is too dark.
You will know the second your clutch is smoking. To add to what Emay said, the smell will be far different from tire smoke.
A burning, or slipping, clutch will smell exactly as if you have a caliper stuck on your brakes.... just like burning brakes. Ever been behind a tractor trailer, and smelled brakes? It's the same smell.
A linelock will not help.... and not that it necessarily hurts. But it's part of racing. Just by virtue of doing a burnout, and racing, you're increasing the chance that ****'s gonna break. It's part of the deal. I know you know this, just sayin'.
I suppose one could say a linelock will help if you are not adept at performing burnouts with a manual car. If you were somehow smoking your brakes, or not getting it done right, then yes, perhaps a linelock would assist in your concentration on getting the burnout done, so yes, I guess you could say that would be beneficial.
As Erin said, the normal lifespan of a clutch is dramatically reduced. By a couple of things:
-Higher horsepower levels
-Burnouts
-Racing
A clutch, even the correct one for your application, just isn't going to last for 80,000 miles like it would in a normal DD car. Not when you're beating on it.
All part of the game brother.