318 power?

I don't think reality always nicely fits into the equations. This coming from a mechanical engineer
The question was which has more potential, your just changing the question to suit how you want to answer it. Of course a 4.03" bore has more than enough potential to build what the average build does probably a 273 3.625" bore is enough bore to accomplish the average guy hp.
A 459 will in most real cases whip a 400, I believe. Lots of guys have proven that with the classic 451.
So under your reasoning engines under 440/454/460 are doomed to lose most of the time.
Equations and calculators often make alot of simplifications and assumptions that just aren't reflective of reality.
That didn't stop you from leaving a statement of oversimplification and filled with a lot of assumptions.

Added, Really that's my point that is there's more to this then the somewhats general statements misleading people to believe Eg. No replacement for displacement, Torque is king etc...