By the way, it seems that the author forgot to mention that one of the 'western' innovations was the adjustable mould. Basically it is a device where you can put matrices of different width, used to cast lead types; in that way you can cast letters like /i/ or /m/ or even ligatures etc. with the same mould. I must add that I don't know if Gutenberg actually invented the mould as we know it (according to James Mosley[] the mould was first described in the XVI century).
It may be helpful to remember that they were not 'scientists' at a meeting. They were members of a committee (Grandi Rischi), part of a government agency (Protezione Civile). They are accused because of their public 'role'. The title is somewhat misleading, it should be: "Italian Major Risks Committee to be tried etc.", if you search in italian press the trial is called "Processo grandi rischi", "Major Risks trial".
(My opinion is that the congress was just a 'public relations' thing to 'reassure' people. The words "the scientific community tells me there is no danger", served, very likely, as an excuse for the 'politicians' to do nothing in order to prevent risks [because of the typical italian cynicism, I can't assure they were not aware of the misuse of their words.]
Please note that after the earthquake the public debate was focused on the stupid problem of 'prediction of earthquakes'. Yes we can't predict earthquakes, but we can predict the effect and take measures in order to prevent risks. And it is clear that nothing was done.)
Leaving more space at the bottom is a technique used to center things 'optically' in a page (the same thing happens when you draw letters like 'H' 'B' 'S'), this is also explained in Gestalt inspired analysis (Arnheim, etc.)
Big side margins were used in manuscripts to allow for side notes, and sometimes in very dense typographic pages margins were filled with printed commentary (for example in religious books), like an heavy frame. Otherwise the big margins could be used for decoration (like in the 'medieval' revival of Morris's Kelmscott Press).
To save space in cheap or small books margins becomes smaller and every margin should be set equal. Therefore the big margins setting is used to convey a meaning of magnificence (for example in Italy, Adelphi uses this pattern of big margins in the expensive books – it is consistent with their 'corporate identity' – and small margins for the pocket version).
The idea of a 'rule' looks like a modern interpretation of a phenomenon (indeed it is often attributed to Tschichold), The so-called Villard diagram itself is a modern interpretation of a small drawing found in his notebook.
The idea of the golden ratio as a perfect proportion, imho, is also a modern one. My understanding of the Renaissance is that they were interested in integer ratios, like 'musical' ratios (1/2, 3/4, 4/3, etc.)
[] http://typefoundry.blogspot.it/2007/04/drawing-typefounders-...