Setting Dragon box FOR ECONOMY

Given that last year's poll on Dragon box settings didn't record anyone with it under 4, I'm guessing this hasn't been discussed much on here, but...

Swiss Family Ap0gee are going to Scotland on holiday soon, and Mrs Ap0gee isn't used to driving my car. Given that it's got something like 100bhp more than hers, and we're going to have a roofbox on anyway, I thought it would be in her interest and our wallets' interest if I reined in the ol' DB. Now I've already discovered that the higher the setting, the further up the rev range the overfuelling goes, but what I want to know is: will putting it on 1 be 'stock', or will it actually be fuelling less than standard (with the performance/economy reduction/increase that ought to bring)? :confused:

If nobody knows, I'll report back after the trip!