Probably not. If the "old" transistor is significantly slower than the "new" ones then the old one will be at 90 degrees phase shift and you'll be measuring the point where the other two average 45 degrees.
You could try designing a circuit that has a consistent 135 degree phase shift and the appropriate gain and impedances on input and output, then essentially measure your geranium transistor's 45-degree current gain phase shift. This suffers from two problems:
1: A broadband 135 degree phase shift? Really? (You can solve this with a PLL, IMHO). 2: You'd be measuring, roughly, Ft/beta. This is actually probably a fairly useful number, but it's not well recognized.