No landowner has ever improved his land. All the improving was done by the people who put their backs into the digging, the hedging and the planting. The landowner came round once in a while on horseback to check that the men were making as much profit for him as possible and keeping in line, but he certainly never acquired a callus or two, except maybe on his arse. Oh yes, he might have built some tied houses and put money into the chapel (that he expected to see his men kneeling in once a week) and built a village hall, to demonstrate publicly what a beneficent fellow he was. But those high rents he charged and the tithes he arranged to collect for church or state were a strain on the workers, who were kept suitably poor, and if the harvest was bad you can be sure that the landlord wasn't the one who suffered. The tithe was a tax all right, paid in goods, but the rent is no less a tax, charged on land that the landlord did not make.

Here's the mindset, Teribus, that still obtains to this day. If you, or your ancestors, were powerful or aggressive enough to take common land, or any land, and have it exploited for your own profit, it automatically makes you a fit and proper person with all the knowledge and wisdom it takes to manage that land to the best of its potential. Well I don't think it does. We end up with vast tracts of land closed off so that the rich can enjoy their "estates" without interference from the hoi polloi and even vaster tracts of land and rivers where they can go and shoot at silly birds or catch salmon, that the rest of us, were we to try it, might have us thrown in prison for or fined for "poaching." And we end up with badly-farmed near-prairies of thousands of acres, growing barley that's fit only for animal fodder for which yer man receives massive subsidies. Insane.

And, once again, the unanswerable point is that not one square inch of any of the land closed off by these parasites was made by them. If I make something from materials that I've paid for, it's mine, and it's all to the good if I can sell it with added value. If I forcibly take something that I didn't make, it's theft, and that can't be mitigated by the passing of centuries.