First off, there’s no getting around the fact that that moment is a gratifying one for a rodbuilder. I often feel like it takes so long to get rods out the door that when the time comes it’s both a satisfying feeling and a great relief (especially if it was ordered a long time ago!).
I can’t speak for other builders, but I do tend to briefly lawn-cast most of my rods. There are exceptions to this — if it’s a model that I’ve made quite a few of, for example, then I already have a pretty good sense of what it’s going to cast like. That’s one advantage of using a beveler, which allows for tremendous consistency in the tapers. But with others I like to take them out and get a good feel for the action and to make sure that the rod is exactly how I wanted it to turn out. In those cases it’s both a last gratifying goodbye, but also a matter of quality control and feedback.
When it comes to fishing though, that’s something I wouldn’t do. Not because I’m worried about the rod being perfectly “mint” when it’s sent off. That’s not the real issue. The real reason is that the first time someone gets to fish a new bamboo rod is something pretty special, and you’d have to be crazy to mess with that.