Mr. Hite's remark was not a theory. It was just an observation based on experience.
Considering the GDXJ is practically 50% down from its highs, the sector has obviously lost significant interest. The anomaly you point out is not specific to our stock. This speaks volumes about opportunity. Currently, there is significant amount of money to be made by investing in the sweet spots of this sector.
One final thought. You speak of the strategy of buying in an uptrend. Trend buying ("the trend is your friend") does not seem to be very amenable to exploration stocks. I am sure it would work to some degree, but I would never buy an exploration stock solely just because it appears to be in an uptrend.
It may do well to reference the following graphic:
Can you imagine buying at the peak of the speculation "trend?"
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