"yet it is painful to see the current irrational price...

"yet it is painful to see the current irrational price action"..this is exactly the thing that has to be conquered mentally if one believes in the long term story I think. IMO..Payback will be progressively no doubt good once things start falling into place..one after the other..like SKI equity participation, Funding for project, mine construction phases, etc..finally leading to first product on ship (by end of 2021)..patience is the key..if one is willing to hold on atleast until production commences, short term price situation can be completely ignored IMHO.
Also the overall market will go thru several upheavals and corrections and that will affect SP, however, markets always correct themselves long term despite several major crises.
The last major crisis..20006-2007...took only a few years to get everything flying again. Key is to hold the rudder steady and maintain the course until destination is reached...one cant loose unless there is plenty of bad luck with all the companies you have invested in...but then that is life. But most times you would emerge a winner with long term thinking and plenty of patience I think.