That's right....

Just for giggles, i decided to load my (Premiere Pro) captured .AVI file into VirtualDub...
Although it's wrapped in an .AVI, i can assume that it's an MPEG based clip.
File information reads 1920x1080. Of course, VirtualDUb couldn't decode it properly on it's own.

So i loaded it as a DirectShowSource() through AviSynth..Voila, playback was fine...And to top it off, file information showed 1920x1080 again...

Does this have anything to do with PAR?

I think the reason is because of the shape of the pixels. For example, when I use my 1440x1080 footage in after effects, I first have to set up my composition size to 1920x1080 to get the full 16.9 wide look when I output it.

In other words, when I pull my 1440x1080 footage into the 1920x1080 comp, it fits the project window perfectly due to the pixel shape.

I'm just now learning how pixel shape and resolution all works now. That's how you can have an SD piece of footage look 4.3 or 16.9 while both show a 720x480 Res. That sumped me for a long time until I found out about the different pixel shapes.

If anyone would like to further expound on this it would be great as I am still learning how it all works. You can find some pixel/Res info at adobe.com.

My experience with Premiere is that it just assumes ANY 1440x1080 file should be resized to 1920x1080. Similarly, and 720x480 file gets resized to 640x480 by default. You can override this using "Interpret Footage" on a clip. One camera I have actually shoots 720x480 in square pixels, and so I have to constant tell Premiere to leave its footage alone.

You can test this by resizing any file to 1440x1080 in VirtualDub and then loading it into Premiere.

Cheers,
Anna