The highest testing strains are rarely the heaviest yielders, and breeders selecting hard for THC often lose bulk along the way. A moderate strain producing double the flower may give more total cannabinoids per plant than a small yielding record breaker. Yield and potency figures are shown together on https://potentthcseeds.com listings, which makes it easy to spot lines that balance both rather than excelling at one. For a limited plant count, that balance is usually what matters.