I'm afraid there really is no answer and no forthcoming solution from Microsoft in the near future. I've begun to focus more on the daily challenges and the Star Club where you can take your time and not have to compete with anyone but yourself. I'll play the tournament with the knowledge that my time can be completely wrong at times just to see how many I can complete, because completion can be worth more than time in certain cases. If one has a higher score with a high time, one can still rank above those with a lower score. I realize this is cold comfort and it's a shame to have such a nice little pastime completely messed up, but I also play some other games online that take the pressure off of this one. If you are interested, try searching the internet for other solitaire games. I also like one Mah-Johngg game that does not have a timer. that's at http://www.addictinggames.com/puzzle-games/mahjongg.jsp. you might need adobe flash for it but that's all. and they are not always easily solved regardless of what they are titled, but it is a meditative sport for me in any case.
I have to limit my stress over one game because it doesn't help me relax, which is the reason why I play online games in the first place. diamond solitaire is seriously flawed and no one at Microsoft cares, that's all I can say. I hope that you feel better down the line. So when the game asks me if I want to see my status from playing the High Road tournament today I may just say NO. because it added 7 hours to my time while I was busy living my life. <3
cheers,
M Gettinger