I'd estimate a stock LHT with racks and fenders to tip the scales at 30+ lbs. And when you have a bike that can easily take a heavy load, you're likely to bring along a few extra things and pretty soon you're rather weighted down. And then you'll want fatter (slower) tires, etc., etc. . .

--nope- - -27 maybe. . .mines not stock but it's not over 30 pounds

I lighter bike forces you to make the tough packing choices to keep your load light. And then you can run 25c or 28c tires which are much faster than 35c.

--I run 700x28's on my LHT fully loaded (for domestic US touring and commuting ) and it runs fine. . .maybe the definitions of "fully loaded" and "packing lightly" are very very subjective. But mine handles a self-contained load with weather gear, camping gear, etc quite fine on 700x28's- - -although I admit, the wheels are DT Swiss 1.1's laced three-cross to Chris King hubs. . . .

Depending on your budget, you can get a good steel sport touring or cross frame and build it up to less than 20 lbs., a little more with racks and fenders.

--I haven't seen many (if any) sub-20-lb touring bikes. Maybe bikes with braze-ons for racks, but nothing I would consider a true touring bike.