Toasted sandwich; Butter the outside or not?

[MissChief]

My 13 year old son insisted I butter the outside of his Toastie on Monday morning. I must admit this was pretty alien to me as I've never done that in the past. Filling inside (usually Ham & Cheese. Or is it Cheese and Ham? Perhaps another topic for another time!) and into the pre heated Toastie machine.

So I tried it myself tonight and other than getting ICBINB on my fingers it did seem to taste a bit crunchier on the outside and still soft on the inside whereas sans external butter previously the bread goes quite hard in places and very chewy. So, buttered exterior on a toasted Sandwich? Yay or nay?