Why just one fix
Most swings have several things you could change. Changing them all at once means you never learn which change actually helped. Worse, it overloads your attention and nothing sticks.
SwingVantage picks the one fix with the biggest likely payoff for where you are right now, so your practice has a clear target.
The plan, then the retest
The plan is a short set of drills or cues aimed at that one fix — enough to make a real change, not so much that you burn out.
The retest is the honest part: you record again under the same conditions and compare. If it improved, you move to the next priority. If it did not, you adjust. That is how progress becomes provable instead of hopeful.