Yavor Doganov yavor@gnu.org wrote:
so I find it hard to believe that a math book with an invariant section "Dedicated to John Doe, my first student at the Foo University" renders the work non-free.
If it were indeed an invariant section (which it shouldn't be - it should be a Dedication in the FDL's language, as I understand it), then it would poison-pill the work. Neither John Doe nor the Foo University could become a primary topic of the work or any derivation, so if John Doe went on to make new discoveries about that field of maths, then they could not be incorporated and set into their context by updating that text book. How is that free?
Invariant sections may seem like a good idea, just like the advertising clauses seemed like a good idea, but they're a pratical pain in the backside and an easy way to make something non-free by mistake (such as using an invariant section instead of a dedications section) or malice.
The FDL should be nuked from orbit, just to be on the safe side. IIRC, the SFDL is a bit better, although it still has some types of invariant sections (including itself *in* the work, for example) but BY-SA compatibility would leave a choice between invariant sections and TPM-bans, neither of which are good IMO.
Hope that explains,