Paul, be assured the coating on lenses, eye pieces and the like are tougher than people make out.
It is just over the top with some of the suggestions that some come up with in case of damage.
As my signature suggests i have some high end lenses and the like, and they are well looked after but are also cleaned with minimal fuss.
If they cant stand a bit of wiping then they are not worth having, Johnson and Johnson would be fine mate, clean away, and don't be afraid, just use common sense, and don't listen to to many arm chair experts.
Leon