They do, they're really great. I used them yesterday on a VERY muddy race and they saved me a couple times on muddy & grassy corners. They're the first time I've had a tyre wash out on me but then re-engage 2-4 inches later with me staying up. The corners were bad yesterday, you had to ride the flat ones "outrigger" style, it was a hoot actually.
Next step is I need to experiment with how low I can go with them - I ran them at 40psi b/c I was late for the start and didn't have a small pump with me. I've made the mistake a couple times of over-deflating my tyres, learning they were too low, then not being close enuf to the pits to skoot over, put a couple strokes in then scoot back and not miss my gridding. It's all about practicing the pre-race routine I guess.
Nice! Thanks for the feedback.
I agree with you that pressure is very important.
Always try to have a few laps before the race playing with pressure to find the one that suites you best.