Radar Control; is it possible for ATC to instruct track instead of heading?
Radar controllers take wind into consideration when issuing headings - "Fly heading one six zero".

Issuing a track would not be practical. This puts the burden of figuring out what course to fly on the pilot. Not all aircraft have a glass cockpit or instrumentation necessary to easily, quickly, and accurately compute a heading to fly to stay on course. The radar controller knows real-time information, knows the 'big picture', and has practice issuing headings.

Actual position is used to provide separation. Heading doesn't matter for separation.