Export Instruments - Import Audio

OK, here’s a fairly simple workflow:

Create a file at 44/16
Create an instrument track with an instrument plugin (Absynth Stereo, for example)
Create a simple MIDI arrangement for the instrument
Set the Left/Right marks
Export>Audio Mixdown: 44/16, Wav, Stereo, Import to Pool
Reverse polarity on the imported file
Press play

At this point, there should be no sound. This isn’t happening for me. Depending on the VST, there are different levels of phase cancellation - in some cases, it’s not really even close.

If I export multiple versions and import them together, they DO cancel out if one is set to 180 degrees. This makes me believe that the VST output is absolutely 100% repeatable. There are no effects on the master buss or individual tracks.

I’ve recorded for years without actually rendering these tracks. I’ve learned that upgrading software and/or removing instruments and then returning to old tracks really sucks, so I’m trying to render everything now. Unfortunately, the audio does not match the VST.

There has to be something simple I’m missing. Any help is appreciated.