Problem with Open Font Licensed typeface?
The Amazon Kindle Publishing Guidelines (page 28) seems to make a request against embedding open source fonts (if I'm using that expression correctly).
Specifically, to quote:
"Only embed fonts that are not currently available on devices and apps. Publishers do not need to include the Charis font with their Kindle books because it is an Open Font Licensed typeface."
Can anyone tell me the reasoning or motivation behind the Guidelines' request? I would think that if you wanted your ebook read with Charis, it's best to embed it as that would make it available to broadest number of readers, regardless of whether it comes with the device to start.
I'm currently interested in embedding Crimson by Sebastian Kosch, which has an SIL Open Font Licence, in an ebook that I intend to make commercially available. Do you think it's unwise to do so?