Just out of curiosity, you mentioned that this past weekend you where pricing this fare and it was in the 150-200 area. A few days latter it doubled up +++ on you, correct? Any reason why you didn't put the itinerary on hold before hand, then check following date to see where prices are at, if the same or lower then cancel first hold and put new one on hold, if higher then buy the hold. That way you are not on the hook to buy at 300++ range.

Why bother trying to figure out pricing on tickets, they use algorithm to predict supply and demand and what to price. The cost of a direct ticket AA-BB might be higher than AA-CC-BB, other carriers might offer different product. The key is cost, routing.