Still there is no risk (perceived risk that is) in a regular rate of return on cash. Again, perception is everything. I also don't believe in the "only can go up" theory, gravity always takes effect sooner or later...
With that said, I am not saying that this bull run in PM's is done or does not have legs, but I am also very wary of the pitfalls of falling in love with a stock or a particular holding.
As much as I believe things are looking grim for the U$D, I am perfectly happy getting a decent rate of return without the risks on a portion of my retirement portfolio. So I can see how this could/will be tempting for others to follow suit as rates continue to rise.
Never put all of your eggs in one basket and never fall in love with your holdings. I remain diversified and flexible 8^)