Well, tying your labor force to the land should be no basis for a free economy!
Imagine, just shackling your primary economic labor force to an arbitrary plot of land and demanding taxes and work of them?! How ghastly.
Next thing you know, you'll be claiming right to their innovations in the advancement of farming technology. Ill have you know that I shall not be sharing MY designs for soil improvement through the addition of various rock powders and animal droppings for a greater yield in the annual barley production with this stingy, short-sighted lord. That's for sure.
And don't get me started on Johnson's idea about switching out the types of crops grown between plots. There is no way I am going to share THAT idea with a lord who limits MY ability to migrate between estates!