It can be advantageous to undercut depending upon your circumstances. A player that harvests all raw materials can afford to sell much cheaper the majority of the time versus a player that purchases raw materials off the marketplace. This of course is balanced by the time lost to harvest said materials that could have been spent producing finished products to sell. I think the marketboard works very well, but it is much more heavily influenced by time as one thing the majority of players lack is patience.

Obviously if you can produce more supply faster than the demand of buyers then one strategy is to lower your price to sell more at a faster rate. Sitting on inventory always equals monetary loss if you are not selling it at the instant you produce it.