WoW Classic – Should I Use Cleave Instead of Heroic Strike to Reduce My Threat?
Even if it isn’t mentioned in the tooltip, Cleave also generates extra threat (R5 cleave +100 vs R8 HS +145) and costs significantly more rage.
If you are truly threat capped then you are better off using neither, and especially not Hamstring instead which is even more threat than Cleave.