The point of separating the gem is so that we don't have to bump Capistrano's version, every time there's a change to what is effectively a first-party plugin. Sorry if the way I responded at GitHub was unclear.
It's a common theme of my maintainership of Capistrano that people have always asked for a web-based version, in the mailing lists, at user groups and meet-ups, more so since Capistrano 3 as we grow in popularity amongst teams who wouldn't normally have a Ruby toolchain installed on their machine.
That said, we have to strike a balance, Harrow was bootstrapped predominantly with money from my software development agency with some seed funding to see us through a smooth launch and get us the UX help we desperately needed to make a product we could be proud of (pro tip: don't let a bunch of ops guys write a Javascript app.), so we have to figure out if this is commercially viable, or whether it was a wasted endeavour, that puts me in the slightly uncomfortable position of what amounts to advertising baked in to open source tools.
As I wrote on my blog [1], it's a fine line to tread, but so far the response has been overwhelmingly positive.
[1]: lee.hambley.name/2016/04/24/seven-years-under-a-palm-tree.html