Zwego has worded this far better than I am capable of. The bottom line though is plain & simple if one stops & applis a little Thinking. If the two loads start with a different pressure level the one starting lowest has to gain it back at some point or it would not produce the same velocity. So "YES" if the teo loads produce the same velocity to the same shot wt & one has a peak of 4300psi & the other 7000psi, the 4300 psi load will have higher pressure down the bbl. It will in fact most likely have higher pressure "EVERYWHERE" except over about the first 3" from the breech. The higher pressure area of the 4300psi load will be spread out over a much longer length, so it will never exceed the other by 2700psi.
Pressure is of course not the sole factor involved here so it would not be save to say the "Average" pressure over the entire bbl length would be identical, but pressure is the major factor & that won't be far off.
