Though I have a little diversity, the bulk of what I posess is in PM miners for the very reason that you state: Many (PM miners) have gone sideways or even DOWN as gold has risen. IMO, the majors and juniors have been suppressed and shorted.
When manipulation ends, exponential profits begin.
I have been "cruising" alot tonight, so I can't recall where I saw this info, but it was a comparison of gold holdings over the course of financial cycles. Right now we are sitting at less than 1% of investment holdings in gold. I can't recall what the high end of the spectrum was, 30%+ ???? Just think what would happen if we return to the former holding levels. Interesting times for the investor that is in "The right place at the right time", to say the least!
I am going to dredge through where I have been tonight. If I find what I have referred to, I will post it.
GFTA