The big thing that a lot of people miss about gold or any other investment for that matter is that there are long periods in time when you do not want to own them and there are long periods in time when you do.
It is all about cycles. The cycle for gold is based on the confidence in alternative money. Right now most governments and especially the US are being completely irresponsible with money creation and that is why gold is now a good investment for the foreseeable future.
If and when the governments become responsible again it will be time to sell most of your gold investments. I think a small amount should always be allocated to gold.