I think I have a couple of suggestions that may help, but that 10 hours tops thing is not going to happen by a long shot.
First of all I really like this idea, letting nature do the work and you sit back and kick it(for the most part). I think you should break the straw bales up into halves or quarters as well as fluffing some up and making a nice hearty bedding ontop of the whole, this will help kickstart the decomposition, and the smaller sections of straw will breakdown faster. Also to help aid in this breaking down process it would be worth your while to make an effort to bring in, even if its only 5 percent of your sleds load, some good ole compost. Mixed in with the hay, it will jumpstart your pile as well as offer a nice base.
Finally I believe this is the most important step, but by the sounds of how much effort you want to put in, you may not want to do it at all. Make a actively aerated compost and alfalfa tea and dump it on your holes at least once, the more often the better. The tea's 2 components will both help get a rich soil and offer a very fast breakdown time for the straw so that your more likely to have these holes ready by next season. The compost offers an extremely diverse population of bactera and fungi which are natures composters, your just basically multiplying, concentrating and then applying them. The other part of the tea, alfalfa offers a water soluble form of nitrogen which is the driving force behind all of this bacteria and fungi work. The more nitrogen they have the faster and better they will be able to do their job, aka breaking down your straw.
Just thought I'd throw out what I'd do if i were in your situation. Good luck and I really do credit you for thinking outside the box on this one