Its a trading position because your underlying premise is that gold will rise (and i am not commenting on whether this will occur or not), which will support an increase in the share price. So basically you are taking an indirect exposure to gold through gold stocks.
An investing decision might be say:
Look at company A, analyse the fundamentals of the company. Use Porters 5 forces, look at its profit margins, free cashflow, debt position, strategic outlook etc.
Does the company have cyclical earnings or relatively consistent growth earnings.
From this i can get an estimate of the value of the company. Divide the value of the company by the number of issued shares and i get a value per share.
Now because of uncertainty and to provide a margin of safety in case some of my assumptions are wrong, i apply a discount to the calculated value per share. This is my insurance (and like any insurance policy it doesnt always work out 100%, so to put insurance on insurance i dont invest all my capital in a single stock, i hold a diversified portfolio).
So lets say my valuation of company A is $5. But the market price is $5. I dont act because i dont have a margin of safety yet (i havent got insurance yet).
The price falls to $4 and i buy.
Now the market suddenly becomes more fearful and the share price falls to $3.
What do i do?
If this was a trading position, you would be looking at exiting the stock and protecting your capital.
But as an investor i have to take a different course. I have to stand back and think: has anything fundamentally changed in the company, is there some significant change in its strategic outlook, or is it just short term market noise.
If the company itself is still strategically the same (and strategic is the opperative word, i couldnt really care if sales are down a few % points for the quarter, i need to concentrate on strategic issues because strategic issues will dominate the success or otherwise of the company over the long term) then i can dollar average downwards.
Dollar averaging downwards for a trader is deadly (Refer to my post on trading rules). Dollar averaging downwards for an investor is not, so long as the fundamentals of the underlying company are the same.
The question for investors then becomes: at what price points do i dollar average downwards, and the answer is just a question of relativity and personal judgement. If you set the price points in too narrow a band, then you have the risk of building up an unsustainably large % of your total holdings in a single stock (which even for an investor is a big no no).