I'm having some conflicting answers here, I think...
dmcgee1 and archer say:
Each model uses it's own LD for purposes of it's own LD tests (Wait, Spot, etc.).
A model may "borrow" the Sgt.'s (or other officer's) LD for Panic checks, and may borrow the Tac Sense skill of the Leader model, but not it's LD stat for Tac Sense.
But PFC Joe:
If a squad member is within C.D. of a Squad Leader (or passing Officer) they may use his LD value. -PFC joe
As long as they're within Command Distance, any friendly unit can use their Leadership. -PFC joe
and Dragon62:
> Soo... Sgt is within C.D. of an officer, then all squad can use officer's LD for morale tests AND all other LD-related tests (except those that must use personal LD)?
Yes they can. -Dragon62