What effect does cue elevation have on squirt or cue ball deflection?
With more cue elevation, there is more swerve. Also, some of the swerve occurs immediately as the CB bounces off the table with the downward hit. I like to call this “immediate swerve.” This effectively reduces the amount of “effective squirt.”
Squirt really isn’t that important alone (except for near-level-cue shots at fast speed or short distance, where swerve is not a significant factor). What is really important, especially with increasing cue elevation, is squerve (the combined effect of squirt and swerve, AKA net CB deflection). And this varies a lot with speed and conditions. And with higher cue elevations, the swerve effect dominates the squirt effect to the point where the squirt can be realistically ignored.
The vertical tip position also makes a difference. For more info, see tip contact height (follow/draw) effects.