This type of insurance fraud is relatively easy and very common. In my day, most of the boy racers were insuring their cars by having the mother down as the owner and them as named drivers. God knows why the insurance companies never questioned the number of grannies supposedly driving high powered cars. I never knew of anyone getting caught out, but the fact remains, you are not insured in the case of an accident if it transpires you are the main driver of a car insured in someone elses name. And believe me, when faced with a claim, the insurance companies will explore every avenue to avoid a payout, and a scenario like this would suit them lovely! You'll get away with it from the point of view of gardai checking your insurance etc. but not in a crash situation.