During his experiment in Cincinnati Warren distinguished different types of labour:
Adjustments were made for the difficulty and disagreeableness of the work performed, so that time was not the only factor taken into consideration. Warren also set up boards on the wall where individuals could post what kind of services they were seeking or had to sell so that others could respond, and trade among each other using labor notes.
From what I understood about Cincinnati Time Store, it was left up individual judgment of for example how many hours of a skilled labourer A should exchange for how many hours of unskilled labourer B.
Though the store was successful, the problem of equal labor times for different difficulties of work was a concern for Warren. He was never able to reconcile the objectivity of his "labor for labor" prescription — treating all labor as essentially fungible goods — with the subjectivity employed in determining how much time used for one type labor entailed the same amount of work exerted during a different amount of time performing another type of labor. He settled to simply credit it with being a matter of individual judgment.
Given the described reason for its failure, was it also the case in Modern Times?
Wunderlich further says that, even before 1857, more of the skilled workers of Modern Times "were beginning to be disinclined to trade their skills at par without financial gain", and so worked outside Modern Times.
Was it up to individual judgement to trade not at par different labour notes in Modern Times? If trading labour not at par took place in Modern Times, was such exchange more frequent in private settings as oppposed to public square of some sort?