For me and my experience in the forex market, I think that Friday is the day is not good for business, and if left on vacation, as a new year and for Christmas I will not be exchanged nor the bank because the forex remain market these days in the party and if the market is on the side, I know not to act. Fore long term traders there is nothing like worst time to do trading , as they place an order with more than one day time targeting good amount of profit there time will always help them. Hence i do not see any time as worst for me, instead i just do analysis place order on market and wait for the profits.