Hello,
I dont know Crabby personally, but we've played together on public/mixes loads of times during the last few years. He is a good player with at least 9 years of playing experience. This doesnt mean he can't cheat, but it proves his gamesense is way above average.
Ive seen the demo's. He is keen, going for the kill. his crosshair moves directly to the players position whenever he crosses a corner. NOT because he saw the player there with WH, but because in 90% of the times he could hear the enemy, and the rest of the times, its just common sense.
I do not believe he used any hacks. The situation in crabyy11.dem -> 10 t's packed up together outside B tunnel, all firing their ak's, just waiting to get killed. 2 flashes..and everyone dies. you could easily tell where the t's were hiding.
SS looks clean.
Conclusion - i dont think he cheats/cheated
goodluck
Legion