Would it help us I wonder if each item of the small details were explained carefully before the policy is purchased
Probably not. For one thing, there are just too many possible situations in most cases. I've have both bad and good experiences with insurance companies and certainly there have been occasions where I've lost thousands of pounds ('fully comprehensive' car insurance can be less comprehensive than you think, for example) but I don't think there's any easy solution to the 'small print' problem.