For a terrier maybe, but certainly not for a cocker spaniel. Handstripping a cocker is by finger and thumb only.
A terrier's coat is far more wiry and can withstand a stripping knife, the softer coat of a cocker would break.
I know you've been putting a banded comb through Ollie's coat, but if you want to have a go at hand stripping yourself then put on an old pair of rubber gloves (old ones have more grip) and as above take some of the coat between forefinger and thumb and pull, don't be afraid to use a bit of pressure and if any is ready to come out, it will pull, if it isn't, it won't!