A workout after a 3000 should not be threshold work. You are already stressing the lactate system from any race in order to metabolize the lactate for energys. You need to run fast intervals after 3000 to utilize the lactate metabolic response. Could do 800 cutdown or repeats of 600 and less for someone like you. FAST repeats from 5k to mile pace
Gjert Ingebrigtsen doesn't support that suggestion. After a tough race Jakob and his brothers ( and a sister! ) sometimes do short LT workouts with the idea to recover faster before next race .
No really fast reps.