The other answers here are all great, but in order to help answer the question as you posed it I'd say that the "Strength" of the Vampires as you've listed it is correct, but doesn't relate to Inhuman Strength, but rather what counts as meal for them:
Black Court > Red Court > White Court
That's correct from a certain point of view. However, I'd encourage you to not think of that list of greater than's not as Top End Strength, but as an Endurance Rating of sorts of Said Strength.
In the Books, Harry describes a situation where he saw Thomas, a White Court Vampire, go one on one with a Black Court Vampire and he was very impressed. He goes on to state that it was largely due to the fact Thomas was "Very Well Fed". Later on, Thomas isn't feeding as regularly and can't push as hard.
Thus, think about it like this: White Court, Red Court, and Black Court can all bench press motorcycles, but the number of times they can do it is related to their Feeding Dependency.
Let's face it, finding the exact correct emotion, inspiring it and feeding on it is more difficult than just killing and eating somebody. Thus the well of energy each type is working with comes with it's own issues.
Black Court Vamps go with blunt attacks and rip victims apart and drink their blood. It's straightforward and doesn't require subtlety, and as such Black Court Vamps have the easiest method for filling their metaphysical gas tanks. Thus they are metaphysically "Stronger" in this regard. It also means Black Court get found out more easily (piles of corpses) and go through their food source faster (fewer people not in said pile).
Red Court works an addictive narcotic angle and can feed on anybody they can lick or get their saliva on for the most part. Technically, it's more subtle and more difficult than just ripping somebody's throat out and quenching your thirst—like Black Court—and is a bit more difficult. That said, Red Court generates fewer mass graves of exsanguinated dead bodies (but they still kill regularly).
White Court has the biggest hoops to jump through to eat. Inspire a compatible emotion, dodge all those with True Opposing Emotions, engage the victim closely and rip their life force away by contact. It's the most difficult feeding aspect of the Vamp Courts that we know of.
Thus White Court has to pace themselves a bit more than Red Court, and Red Court has to pace themselves more than Black Court; because, each respective methods of refueling is more difficult. Sure White Court can be just as strong as a Black Court, but they better have their next meal ready.
I think the idea is:
White Court needs to pace themselves more than Red Court.
Red Court needs to pace themselves more than Black Court.
Black Court doesn't need to pace themselves as they'll eat any human they can overpower.
I hope this helps make sense of their relative strengths.