"at the top of a value curve" indicates to me that OP is expressing that he is imagining Gates seeing Microsoft's value as a line that will curve downward after this, or at least flatten out. I could be completely wrong.
So what I was trying to express to OP is that while Microsoft's value may not sink (that is, now is not at the top of any curve), the value of the investment may be rising faster in various measures than the same money in Microsoft would be.
So what I was trying to express to OP is that while Microsoft's value may not sink (that is, now is not at the top of any curve), the value of the investment may be rising faster in various measures than the same money in Microsoft would be.