Norsk Hydro: big theme, positive charts...but I cannot quite buy it

As an investor it is important to figure out relatively early in your investment life what you are better than average at...and what you are worse than average at. 

As a global investor who often cites themes and bigger picture macro influences in theory I should like a story that has historically underperformed...

...is seeing a supply/demand imbalance (i.e. supply is currently less than demand and hence inventory levels are falling)...

...whilst the underlying commodity price linked to almost all of the products the company sells is going up: 

Finally there is rising thematic demand from many big industry groups including the auto sector:

However in the case of the aluminium industry and the Norwegian company Norsk Hydro in particular (all the above charts were taken from today's capital markets day).  I just cannot get comfortable.  I like a turnaround story but one where (unlike say the miners) I am not getting a 5%+ dividend yield or (like the food retail companies) it is not a necessity product with lowly variable demand.  Additionally - and despite the early mentioned multi-year lack of performance - the shares have flown this year as noted below (helped recently by the above plus the weakness of the Norwegian currency due to the issues in the oil/gas markets).  

I even have been short Norsk's peer Alcoa at various points in 2014 which - to be blunt about it - was unprofitable (unsurprisingly given that Alcoa has outperformed even Norsk Hydro in local currency terms over the last year)

My 'issue' is one of valuation, the large number of inherent uncertainties and (more latterly) the upward movement of the share.  Clearly some people have made some great money out of this stock and I just do not apparently have the right mindset to do so.  

No hassles, no issue.  Plenty more stocks to look at.  Reminder to self: be as cautious in shorting the stock as you have been in buying it.  Blindspots often work both ways.