Reading a fiddlesticks guide the other day and the guide writer says how you should always invade at level 1. He mentions that most teams don't defend their jungler and even if they do you can usually surprise enough to get a kill.

I assume this isn't the same at higher elos but I think he's actually totally right at 12-1300. Does anyone level 1 invade frequently? If so, how does it end up?