definitely. I learnt to crab pretty early into my scratch development, and as a consequence didn't spend much time on chirps, flares or transforms to get them nice, so everything i do is fairly sloppy. if i was god i'd have banned crabs and customs. i did the same. i still havn't got tears cleanly to this day because all i used to practice were crabs when i first started. i got them down within the first year but realised it was just messy and sounding like i was trying too hard to sound fast, because crabs were the only thing i was doing. i then used my newfound hatred of crabs to perfect my orbit/flares.. and now i barely crab/twiddle at all.