This happened recently in the sim: while going back to departure airfield in emergency, the Captain passed the control to the FO.
The FO deployed half speed brakes because he felt he needed so.
The Capt. took control again, just before intercepting the LOC.
He hadn't noticed the speedbrakes were partially extended.
As a result, they flew the whole LOC- circling approach with the speedbrakes half extended!
ROFL
Had they been fully extended, that would have been noticed.
On more modern jets, a master caution is triggered if you advance the thrust levers with speedbrakes extended.