BeachRunner...we've had goog success in just using the butter and drizzling with a bit of really good olive oil at the end. Yeah, the older recipes really go to town on the oil! Post back when you have your recipe perfected!
As for deveining, I always devein very large shrimp , just because it's fairly easy to do and usually a larger shrimp means a larger vein and it LOOKS bad. That said, I grew up around here, eating off the shrimp and fish boats and we never deveined our shrimp. However, some hauls of shrimp have a sandy vein that really ruins the shrimp experience -- kind of like how some bags of mussels are sandy and some are not. Maybe someone with more knowledge of local shrimp beds can give us some insight as to where or when the shrimp are most likely to have a sandy vein. I'm sure there's some sort of science to it. I'd really love to know...