Fun fact, wrote some walk with fastai articles on just this 
Exporting your tabular pandas object: Exporting `TabularPandas` for Inference (Intermediate) | walkwithfastai
Using custom statistics: Using Custom Transform Statistics (Intermediate) | walkwithfastai
More is to come, just need some time after midterms to actually make the rest of what I have planned happen.
Oh goodness no. I never ever do that for general debugging. Too much time wasted trying to reinvent the wheel. I look at the last 3 blocks from the stack trace and that can paint a pretty good picture. In this case pandas was using too much memory which gave me OOM errors. Checking the init for Tabular showed that fastai would override some datatypes, so there was an interim PR (at the time) which fixed that some.