This is out of my league, but I will take a stab at a few of those questions. The RWHP, generally, is a better measurement for dictating what's safe and what's not for a stock motor, pending safe tune. You could make that statement a lie by simply saying "OK, lets put a cam in and rev a bone-stock motor without FI to 12,000 RPM's to make a "safe 450 rwhp"; boom. That being said, if you have 10 psi with a blower, then put a big cam in, the higher lift and duration will let the engine flow more which reduces boost as that is only a measure of restriction anyway. Same thing happens with long tube headers and high flow cylinder heads. THey flow more, they reduce boost numbers. As far as "is it safe to increase boost again after that", if you were at 500rwhp with just 10psi pre-mod and then put that big cam in, it may lower the boost, but your rwhp is going to go up if it's a decent cam and been tuned accordingly. You have to figure that you're moving more air, which needs fuel, which creates a stronger combustion which will accelerate the piston/rod/crank and at a certain amount of energy is going to let go (stock) whether you are at 5psi or 10psi. I think (guessing) what you are trying to get at is - is all horsepower equal? Can you get away with more horsepower if the boost is lower via higher flowing components. And MOST definitely, there are a lot more educated answers to be had. There are a few guys here with seriously built engines. Hopefully they will give their input.