It definitely helps to have fast, sticky rails. The spin needs to grab. But don't be ashamed of the slightly random shot that went. That's natural for this proposition. I think Massey got a little lucky when the CB drifted forward.
Thanks! I can see that. I'm on a bar box with felt that's a year old. It's starting to slow down some. I felt like I was getting more than enough spin. I think I just needed the One to either hit the cueball with more force or hit the cueball more square. It was interesting watching the variables in play.
Move the One-ball up the rail
You can come into the One-ball with a wider angle and get more force, but the two-rail path gets harder to line up.
Move the One-ball down the rail
You can come into the One-ball with a narrower angle and the two-rail path lines up easier, but you lose speed.
Hit the ball harder
The One-ball has more speed except now the rail compresses more and the One ball tracks as a bank instead of a two-railer. You then need to compensate with a narrower angle with in turn bleeds off some of your extra speed. It was difficult to hit with precision with a longer back swing. I had better luck with just more emphasis on follow-through and positioning my back hand further back.
Hit the ball softer
This only helps if you're already hitting it too hard. The One-ball has less speed so the rail compresses less. The One ball tracks more easily to the two-railer but you may find it doesn't have enough oomph to get the cue ball to the Nine-ball.
Aim slight more right
If you're seeing the Cue ball follow the rail up the table, you need to aim more right. If not, you can still try aiming more right but you'll need to hit a smidge higher to counteract the tangent pulling you under the One-ball into the rail and drawing out of there. I had trouble seeing this result helpfully.
Aim slight more left
If you're seeing the cue ball catch the rail right away under the One ball, you need to aim more left. If not, you can still try aiming more left but you'll need to hit a smidge lower to counteract the up table drift. This was helpful sometimes as an option to effectively hit a wider angle and have the One ball come back with more speed without having the cue ball higher up on the rail. It was hard to reproduce consistently as and adjustment without flubbing the balance of cut and follow.
The whole night was spent making combinations of compensating adjustments, trying to execute the adjustments properly, and learning with combinations helped some and which didn't make sense because of some unexpected factor.