Steve,
Neat system.
I suppose it has the added bonus of keeping both hands free while rigging. Something well worth considering.
Just a little concerned that body heat may take the edge off the chill in the beer.

I suppose that wouldn't be so much of a problem if you filled it with rum.

Regards,
Phill

I know that the voices in my head aint real,
but they have some pretty good ideas.
There is no such thing as a quick fix and I've never had free lunch!