You can, and indeed many direct-drive hub systems include this, but it's not a range issue. It's more to save some brake wear. In a 'best case' scenario of ma

You can, and indeed many direct-drive hub systems include this, but it's not a range issue. It's more to save some brake wear. In a 'best case' scenario of many steep hills, such a system will extend range perhaps 5%. Much less in normal use.