Did I imagine this, or is there a contribution guide somewhere that advises contributors to not rely on the GitHub CI and instead test locally before pushing? I understand why that is the case—the only reason I bring that up is because I want to see that entire document again and this is all I remember from it. I’ve seen the contribution guides linked from the README.md.
The main contributing doc is: pytorch/CONTRIBUTING.md at master · pytorch/pytorch · GitHub
I am not sure we recommend not to rely on CI though.
The main thing might be that CI testing is slower than doing the local checks. But CI will cover a lot of configurations that you (most likely) cannot test locally so it is very important today.