I find the Garmin Catalyst truly helps WHILE you are on the track, as much as after you make a run. I can Ghost another Catalyst user's data and lap while I am on the track and see what their line is in comparison to mine. I also know at each sector if I have advanced my delta or wasted a run and should just give the car a cool-down.
Here is my run from Barber Motorsports Park last month.