During today's practice session, I did some one-rail testing with two different methods that I found the most promising for the most common range of shot angles:
1. Top spin, soft rolling speed, using the diamond line as a mirror
2. Top spin, varying shot speed by a combination of knowledge and feel, using the "true" mirror point as a mirror
My setup was the following:
Yellow line = diamond mirror line
Red line = "true" mirror point (the point where the cue ball's center is on impact)
Six different cue ball positions, all 1 diamond off the long rail, starting from 0.5 from the long rail and going 0.5 forward each time until the 3rd diamond.
I did each of the 6 shots 4 times for both of the styles, so 24 shots per style. It should be noted that I didn't use any chalk on the rail or other external tools to aid me in sighting to the mirror points, I checked/memorized/aimed at it just like I would in games (within a reasonable time, takes me around 20-25 seconds when done carefully for the whole execution from walking to start finding the mirror line to shooting the ball), so there obviously will be slightly more random results compared to using a marker, but I'd say I'm pretty good at seeing and keeping that line.
The results were the following:
With style 1 (soft rolling speed):
8 pots
13 hits
3 misses
With style 2 (varying speed with feel/knowledge):
7 pots
17 hits
0 misses
Observations:
- I'm not entirely sure why I missed 3 times with the rolling one, it didn't seem like I aimed them wrong or rushed my fundamentals. All of the 3 misses were from the two leftmost cue ball positions, and were just barely missed, none was way off. Maybe I shot them too softly, and it has an effect? Or perhaps the soft speed causes the cushions to me more prone to behaving more unpredictably due to imperfections in the table? No idea at all, just guessing here. I wouldn't say that the two leftmost cue ball positions simply require an adjustment, because I also potted from them 2 times out of 8.
- Both methods were missing roughly equal amounts to both sides, which is a good sign.
- Both methods seem to pot the ball roughly 1/3 of the time for me from that distance.
- For both methods, I had more pots the closer I was to the 8 ball, or in other words, the smaller the kick angle was. This isn't too surprising, especially with rolling ball I had a vague expectation that it's most consistent for smaller angles.
- I never missed with style 1, even though I used varying speed, which in the original post, I considered might generally be a bad idea over varying your aiming offset or tip position, but it works well for this specific shot type at least. This is the method I've been using the most for many months now when faced with a kicks where I try to pot the OB, so I guess the experience pays off as well. The larger the kick angle, the harder you need to shoot, and past a certain angle+distance, you simply can't aim harder, and therefore need to start adding an aiming offset to compensate for the larger curve. All of the shots in this experiment were small enough to not require that aiming offset.