Yes, Drag Times uses the reported barometer (which is corrected to sealevel). They have the track's elevation and their calcuation changes the reported barometer to actual barometer based on elevation (like I did).

And their numbers are useful if you have no track measurements. But since they are not temp and humidity from the track, they can be off the actual due to local conditions:
-the airport cools/heats faster/slower than the track
-the track's pavement (acres) might cause locally higher temps
-the track's location might have different humidity (nearby river, lake, etc.
IMO, the baro correction is pretty good (if the track elevation is correct) since that doesn't change much over 10-20 miles. But clouds can shade the track (or airport) and with the pavement have 5-10 degree different temps (worst case)