Stretching

Has anyone seen quality gains on just a daily stretch routine only?

People have yes. But most would recommend you still do some light jelqing a few times a week to keep your EQ up to par, as a lot of stretching can affect that.

My own humble opinion is that if you are after length gains mainly, you should put your effort into stretching and keep the girth work to the minimum. That is what I am personally doing right now. I am stretching 5 days a week and doing light jelqing 3 times a week.

Even though jelqing can also be beneficial for length, it is a girth/length exercise and primarily girth. I think most people agree that all sorts of stretching methods is where you will find the length from.