Is there an easy way to strip twin and earth cable?
There are tools which do the job for you. They will probably take a little adjustment when first used, but then they're fine. They are literally the easiest way to consistently strip mains cable.

Many years ago my father had a hand-held tool explicitly for stripping Australian 240V household wiring cable. It had two clamps, two blades and a two-part action. The first clamped the cable and made the cuts, the second separated the clamps, neatly stripping the end off the cable. 

(I should add that I don't strip cable every day but I learnt how to use a small but very sharp pen knife to strip outer sheaths. A bit time-consuming, but I like doing it that way as it works on any sort of multi-core cable. And the trick to not nipping the conductor is to not cut quite all the way through the insulation: let the stripping effort break the last little bit.)