FATE core specialised skills

I discussed one method of dealing with specialised skills in my Warhammer 40K FATE hack here :
However, as FATE core encourages the GM to have the players take a more active role in determining the outcome and progress of the story, I also like to discuss the various permutations of the rules with my group before implementing them; last session we discussed how certain skills (such as craft, drive and lore) could be made more specialised without unduly complicating the rules system.

Eventually we hit on the idea that someone would still have their generic skill level (set at whatever level as determined by character generation) in lore, drive or craft and that people without would roll at Mediocre (+0) level as per the normal rules, but that each person with this skill would choose their particular speciality and note it in brackets after the main skills.

For example:
  • Drive (aircraft)
  • Drive (space vehicles)
  • Lore (Imperial Religion)
  • Lore (The Warp)

The speciality functions like an Aspect tacked on to that skill and can be invoked in the normal manner by spending a fate point; this effectively gives the character a small bonus in their area of expertise but only if they’re willing to spend a fate point.
The addition of an extra Aspect tied to a skill doesn’t unduly complicate the rules and my players seemed to find them easier to come up with since the skill already gives some ideas of what to take; it is also an idea that can be used to add some additional flavour to the basic skills list without introducing a shedload more skills or making the rules unnecessarily complex.
For example: Instead of introducing a Medicine Skill in my game there is the Craft (Medicine) ability that functions as per normal Craft skill but allows the expenditure of a fate point to Invoke the Medicine Aspect whenever appropriate.