Probably find paying £0 on insurance for two years is better than any NCB discount
Quite probably. Theres also something called NCD mirroring now too that helps take into account the driving records or people who are not the named insurer on shared vehicles. So although you lose the NCD if you’re still driving on other people’s insurance then if you re-insure yourself later some insurers will take that into account – at least for the first year or so, but as above the value of your NCD isn’t always that clear and once you’ve got a couple of years again you’d probably not notice the difference between that and 10 years discount.
NCD mirroring might depend on you being a named driver though – if the business insurance is just a blanket any driver insurance that she’s not named on mirroring might not be applicable.
Unless you’re a young / inexperienced driver then the discount isn’t going to be a huge amount of money to lose sleep about and its going to be less than the cost of one years insurance so if its a worry just put the money you would have been spending on insurance into a savings account and treat it as your own NCD later.
who says its fully insured with his business
You might want something a bit more concrete than his say so – I’d at least want to see the policy and fully understand what the exclusions, excesses etc are – especially as its a business policy and your wife isn’t an employee.
“The large print giveth and the small print taketh away”