Everyone has good days and bad days but the difference between us is I believe the majority of those fluctuations in play are caused by stroke errors more than aiming errors. Nervousness in a pressure situation clearly impacts the stroke mechanics more than the aim. If you are nervous and miss a straight in shot it isn't because you couldn't see that the correct aim was a full ball hit.
What you are getting at without saying it is that CTE eliminates the problem of having your eyes not seeing right from day to day. That's why you said, "That's what I don't want to have happen." The problem with your logic is that if the eyes won't let you see what you normally do with ghost ball aiming, they won't let you see your two lines properly using CTE, either.
Exactly. These same physical and mental stumblings occur regardless of aiming method, including CTE. On a day when your eyes aren't working to full potential, or your mind is not in the game (which is the real problem, not the eyes themselves), when you aren't accurately visualizing ONE line (like ghostball or fractional aim line), or your feel for speed and spin is off, to believe you'd magically be able to visualize two lines any better is illogical.
I will say, however, that focusing on a solid psr can magically smooth out those stumbling blocks most of the time. I've found myself off a bubble, not playing up to speed for whatever reason -- pissed off, stressed out, wore out, upset, headache, etc...(the list can be endless when we're looking for an excuse), but now I simply start thinking...
ok, this ball is on 36, I'm lined to 15. If I were lined to 18 this would be a half ball shot. 13 to 14 would be a 5/8. So this is a touch thinner than 5/8.. This all happens in less than 5 seconds, then I decide where the cb needs to go after it hits the ob, make my aiming adjustment to account for that, and drill the shot.
By narrowing the mind (focusing on something specific that leaves your excuse out) you can get back on track much easier, back in stroke and up to speed. This can happen with any aiming system or method as long as you incorporate it into your psr. So maybe that's what Spider is getting at, the reason he hinted that CTE keeps the road smoother for him. I can say Poolology does that for me. But when you're really playing, having a great night, in the zone, free and easy, the actual conscious effort is happening so fluently that it's really being orchestrated by the subconscious. So for me I'm not looking at numbers or fractions or anything...I'm just playing. But if I feel like I'm running off the rails, struggling, then I have system that I can focus on to get me back on track.