I'm not sure Zeiss was concerned about the weight of the 56's. Heft helps stability (inertia and all that), and as a 10x is relatively difficult to hold steady, the lighter it is, the tougher to get the good view. Learning to hand-hold a bino over 10x or so takes a while, unless you are a rare physical specimen (that say takes no more than about 6 breaths per min and has a relaxed pulse of maybe 20 per min) and have substantially higher than normal powers of disciplined concentration. (Steve Ingraham had a couple good articles on this in BVD). So perhaps these two (and maybe more to come?) weren't intended for the beginning bino customer (the size, wt & cost would be immediate deterrents), but rather for the user who knows fully what he (or she, as the case may be these days....)is about. Much the same case would be a beginning shooter getting something like a .300 Weatherby (or whatever) as a first rifle after shooting his dad's .30-30 a few times....the first shot taken with a 200 gr factory load will be painfully remembered for a lifetime (and unless said shooter is very determined and has a stout constitution, a second shot likely won't be taken, due to the thunderous muzzle blast and about 50 ft/lb of recoil...about like having Tyson hit your shoulder full force, bare knuckled). Or a novice handgunner, after practicing a little with .38 target loads, picking up a .454 Casull, .50 Desert Eagle (etc), squeezing off a full charge 300 gr round, resulting in a dent in the forehead and a hand unusable for a couple days. A neophyte motorcyclist, fresh from learning on a Honda 250, hopping on, say, a VMax (again there are others), droppin' into 1st, grabbin' a handful of throttle and suddenly realizing the front axle is eye level (& going higher) and lots of things are happening REALLY fast...this can easily cause temporary cardiac arrest, possibly wet britches and in all likelyhood, a pantsful.
Now these may be extreme analogies, but the idea is, some consumer products aren't meant for all consumers. Most beginning birders will usually go for a more common 7 or 8x by 35-40....we here, being more discerning and knowledgable, are open to the wider range of available optics (some might say lunatic fringe) in search of some sort of....I think the term "optical nirvana" was coined in a previous thread, and understand the various ramifications and vicissitudes of the less mundane optics, i.e, the "rare air of the magnification stratosphere", to put it cryptic terminology......(sorry....this probably should have been put in Tero's binocular ramblings thread....oh well, too late now)