If they don't have a source: how would they? Unless they are a source, they have to get the merit from somewhere. A group of accounts without a source can't generate merit without making good posts; they can only inefficiently spread it out among the accounts.
But old account farmers who have Senior+ accounts at the moment and therefore sMerits can give merit to their new accounts, who would have 50% sMerit to send to other new accounts and so on?
Of course it will stop at some point but there should be some way to stop or reduce this, by detecting the same IP, circular references, or granting merit to obvious poor quality posts (although the later would be harder to do automatically)
But definitely it will be harder for farmers to have new accounts with a high rank. I see an increase of prices for accounts being sold :/ ...