[SunkenCiv]

:’) I picture them as slow-movers, and having a dry alimentary canal, and look to the great whales as examples (since they swim via their own motion, and are larger than the dinos) of what muscle, sinex, and bone can accomplish. :’)

[Fred Nerks]

Neck Posture and Feeding Habits of Two Jurassic Sauropod Dinosaurs,

Dinosaur studies (neck mobility, posture, etc.)

Doesn't deal with the weight issue - but the graphics and images throughout are brilliant...lots of spines and necks!