Metabug so that I can explain why I'm doing this when I have to point people at it in the future... If a vim syntax file uses 'highlight link' (or 'hi link'), overriding things on a per-user basis is tricky. It's better for plugins to use 'hi def link'. This is the same as a normal link, except that the user can override it with 'hi link' in their vimrc. Relevant help text: hi-default
Think we're clear of these now.