That one precondition is like the equal amount of playmoney every player gets at the start of a Monopoly game. If there were five kids gonna play Monopoly and Jimmy, Suzi, David, and Lisa all got $1000 apiece and little Billy Gates got $51,000,000,000, you better believe that the first four kids wouldn't even want to start. Timesizing comes as close as it can to free-market (everyone-involving) definition of the precondition by involving every player in the process of determining the fundamental market precondition - on an ongoing basis. It does this via regular, binding, public referendums that give every market participant a chance to put in his two cents' worth, just as the real market does once the precondition is set. A referendum "seeds" the whole precondition setting process.
Timesizing seeds the game in the least-controversial way by polling public sensitivity to the worst potential problem of our economic lives - unemployment and inability to self-support. By letting the public define the downside (under-employment) and letting the downside determine the upside (overtime) via an incrementally changing workweek length, and letting the upside determine its own resolution (overtime triggers training and hiring to obviate the overtime in future), a resolution that simultaneously resolves the downside (under-employment), timesizing solves the market predefinition challenge in the most market-like way and makes a start on the wealth concentration problem by solving the work (and skills) concentration problem.