[Groff] Kernpairs and hyphenation

[Tadziu Hoffmann]

I just noticed that groff wouldn't hyphenate "fragment" into
"frag-ment" in Times-Italic.  (In Times-Roman this works.)
Turns out this has to do with there being two kernpairs, "ra"
and "ag" -- if I remove either one from the font definition
file the word gets hyphenated correctly.

Before I try to wade through the code myself, I wanted to ask
on this list whether any of you have a guess as to why a double
kernpair would prevent groff from seeing the breakpoint...?



PS: Happy New Year to you all!