Hi
On the other hand, even some "Western Europeans" may enjoy for example using true smallcaps (coming from embedded font). These can be added with as few as 60k to each EPUB. Even if smallcaps represent probably less than 1% of the EPUB text content, I think they are really nice looking and are a worthy addition (see screenshots below).
I checked that these true smallcaps can be properly displayed both on ADE (contrary to the - fake - font-variant: smallcaps) and on my old PRS-505.
If they are not seen by some ebook readers, what happens? Will these ebook-readers display a standard default replacement font ? A user-controlled one? I can live with that.
If they crash the EPUB, it would be a different story, and it would make sense to provide two EPUBs, one with them, one without.
To make a sound decision about this, some down-to-earth information of this kind would be needed. To condamn it on principles is a little like refusing to add salt to your menu to avoid coronary diseases. Sure, it's an extra step (adding salt too...). I understand that sometimes it could be better to avoid it.
But when? For whom?