Swooping doesn't do anything but make it harder to hit the correct spot at the correct angle.
I am not a fan of swooping, but it can offer advantages to some people, as listed on the
swoop/swipe stroke resource page. Here they are:
1. A swoop stroke allows one to aim and hit closer to the center of the CB, to apply sidespin. This effect doesn’t allow one to put more spin on the CB than is possible with a straight stroke, nor does it change the effective miscue limit (or the maximum amount of spin possible), but it does allow one to hit the CB with less “apparent” tip offset.
2. The sideways swiping motion (especially if it is fast in comparison to the forward speed of the cue) helps provide slightly more
squirt (cue ball deflection) aim compensation than is provided by a
pre-stroke BHE pivot. And if one uses a
non-LD-shaft (especially with a
long bridge length), this slightly extra squirt compensation might be helpful (assuming they haven’t already adjusted their aim and alignment to intuitively
compensate for squirt, swerve, and throw, as most pros and top players do).
3. A swoop stroke can allow the cue to be aligned closer to the direction one wants the CB to head (assuming the aim compensation provide by the swooping motion is appropriate for the amount of squirt, swerve, and throw anticipated for the given shot). This could make it easier for some people to visualize the line of the shot and one’s aim and cue alignment. Without a swoop, to compensate for squirt, the cue alignment at address would be off center and in general not in-line with the desired direction of CB motion. Most top players can aim and align the cue in this fashion intuitively, and it is comfortable. However, some people find the off-center and off-line pre-stroke cue alignment to be disconcerting.
4. A swoop stroke allows one to apply
BHE squirt correction during the stroke instead of before the stroke. BHE before the stroke can be awkward, uncomfortable and unnatural to some people. Some, while aiming and aligning a shot, don’t like seeing the cue pointing in a different direction than they want the CB to head. Also, some people don’t like to change their stance (which can occur with a pre-stroke BHE pivot) and cue alignment after being down on a shot.
Regards,
Dave