Most insurers will allow you to retain your no claims discount for up to two years.
So, theoretically, your plan to insure your car in different names (on alternate years) is a sound one.
However insurers are always watching out for cases of illegal 'fronting', whereby (in order to save money) the person who actually drives the car most is only a 'named driver' on someone else's policy.
While you might not actually be engaging in 'fronting' it's likely that swapping the main policy holder backwards and forwards could lead to such suspicions, with the insurer refusing to pay out on any claim you may make (other than as required to do so by law).
That could result, for example, in you paying for 'fully comp' cover but finding that the insurer would only pay out at the 'third party' level.
Chris