He claimed that sidechains do not provide a useful compromise and add complexity and huge delays. However, Jeff Garzik responded by saying that although he agrees with the added complexity of sidechains, they can be a solution for scaling long-term. Jeff compared sidechains to git repos and merges, where having aggregation chains that arbitrarily fork and then rejoin the main chain is feasible and useful. While this solution is still a ways away from production, Jeff believes it should not be dismissed as a solution for scaling in the future.