I wouldn't give up completely on test rolls. If, for instance, you want to try a new developing technique (maybe stand development, or varying time, dilution, temperature, whatever) it makes sense.
Just take pictures of a standard, reproducible test scene, not once in a lifetime events!
I usually take a few frames of my standard test scene (a room in my house lit only by its overhead lighting), then go in the darkroom. Without rewinding the film, in complete darkness, and open the camera back. I remove only the exposed film, and wind it onto a reel for development.
The rest of the roll can be used as normal once I use scissors to cut a new leader.