IME the worms are a get-you-home option; on MTB tyres it doesn't matter that the worms poke out, as the knobbly tyre bits compensate for the protrusion, but on a road tyre you really fucking notice it, regardless of the pressure. In a perfect world you can cut them so they're just sticking out (they flatten over time and go hard, once you've doused them in solution), but you have to get a good sharp blade because it's quite easy to accidentally pull the worm back out.
Oh, and like a previous poster suggested, you can trim them vertically and horizontally because the size they come in is often far larger than is required to fill the hole.
I've found worms from motorbike kits to be really sticky and bed down really quickly. Only happened on that by chance when I was carrying the motorbike kit in a frame bag and needed repair.
IME the worms are a get-you-home option; on MTB tyres it doesn't matter that the worms poke out, as the knobbly tyre bits compensate for the protrusion, but on a road tyre you really fucking notice it, regardless of the pressure. In a perfect world you can cut them so they're just sticking out (they flatten over time and go hard, once you've doused them in solution), but you have to get a good sharp blade because it's quite easy to accidentally pull the worm back out.
Oh, and like a previous poster suggested, you can trim them vertically and horizontally because the size they come in is often far larger than is required to fill the hole.