Dog Day Friday, page-6

Short answer, open is not the most profitable endeavor.

Unless you are intimately familiar with auction theory, prospect theory and understand how the opening works, you would want to avoid trading it. In fact, even if you understand the process, you would want to avoid trading it as your human reaction speed and mental faculties may not be able to deal with the whipsaw as money is on the line.... During the open market searches for direction. On retail spreads, your probability of success is low.

If you don't believe it, try trading the DAX open on demo account. Results may be discouraging