There are many cans o' worms to be opened here. But those photos of lug thinning are useful. When cast lugs were introduced, much less of that was done - cast lugs can be thinned. But it's a little harder than with pressed lugs, and cast lugs were widely embraced in part because they needed less work to be presentable and therefore saved money. The aesthetics of this kind of thing are hard to pin down, and to some extent subjective. There was a school of lug filing following Albert Eisentraut that went for super-thin lugs, which some folks find overdone and maybe a bit showy. Check out Mark DiNucci's work in this tread:
http://www.bikeforums.net/showthread.php?t=339945
Many folks feel that the idea is a degree of thinning that makes a smooth transition between the lugs and the tubes, creating a sculpted, flowing look that over- or un- thinned lugs can't capture. Check out the sculpted quality of this De Rosa, which I used to own (in particular that exquisite lower headlug):
http://www.flickr.com/photos/2358521...7618581982271/
A lot of handwork went into that De Rosa and the DiNucci I posted above. Nothing against the Look frame, but there's much less handwork there (very astute to pick up on the fact that some apparently at least took the trouble to shape the lower headlug).
I personally like the very thinned lug look as well, except when it's excessive. I also like cast lugs when they're very tidy with clean "shorelines" and contribute to the overall aesthetic:
http://www.flickr.com/photos/yangeva...7606035181695/
Very different look Samson is going for (monster framebuilder, by the way - Harada, I believe).
Once you can distinguish which frames truly represent top level handwork, the key is to decide what style/elements you admire and why. There is a lot more to it, obviously.