Wouldn't it by much more comprehensible (and thereby also more trustworthy) to convert the existing blockchain to bcrypt in the proper way, rather than creating a new one and employing some hard to grasp scheme of premining and transferring transactions to the new blockchain. This will essentially circumvent the crypto which we all trust in (otherwise we wouldn't use cryptocurrencies): The transactions were signed cryptographically with amounts decided by the users. Now if you break the scheme to create an 1:10 exchange, you have no way other than going completely without the crypto, thereby forcing all users to trust your benevolence as a monopolist. Discriminating cryptocurrency users do not need to trust a monopolist. They could just as well decide to take the source, fill in other seed nodes and use the other features on a "Community-NUD" blockchain, deciding themselves about a better way to switch to bcrypt if they want, and leaving you with your "Dictator-NUD" blockchain and your pre-mine.