I'm wondering what anyone can say about the accuracy of the Flight History information.

For instance, go to Flight Tracking, Track Flights and enter 28647353. Then zoom in on DFW (the lower left end of the flight). The path is all crazy.

After digging a bit deeper, it appears two things are happening. First is that two different centers are reporting locations, and they are off by a noticeable amount. When put into a time series, it makes it look like the airplane is jumping around.

Second, if you look at the Track Log tab at the bottom, you can even see that center KDFS keeps reporting two locations for each timestamp.

So, there are two questions here, and a bigger question about whether issues like this are common problems. I plan to use the API to pull info like this in the future, but if I have to frequently confront data like this, I'd like to know now.

Welcome to the world of raw FAA data :) When centers/tracking facilities overlap, you'll often get zig-zaggy data. In addition, some centers provide positions that include seconds (whereas most only provide data in degrees/minutes), so some positions are more precise than others - this can also produce a zig-zag effect.

I did double check the raw data from that specific flight, and there were indeed multiple position reports with from the same center with the same timestamp but different actual positions.

In general, we basically always work with the raw data and try to store it "as is" so that we have something that is as close to the original/raw data as possible.