Group-level override?

(This is basically the same idea as #1386, but it appears to have been closed without a resolution.)

I'm looking for some way to override the remote server used when restoring packages.

The scenario I have is as follows:

We have an internal ProGet server which acts as a caching reverse proxy to the public NuGet gallery. This works wonders for internal developers, on-premises build servers, etc.

However, when a developer works remotely, we'd rather hit the public NuGet gallery as it would be faster than retrieving all the packages from ProGet over a VPN.

It seems that we have a couple options, none of which I like particularly much:

1. Write or generate a paket.local file to override the source for each individual package
2. Manually modify the restore: line in paket.lock, taking care not to commit the modified file.
3. Modify the server URL in paket.dependencies and re-build paket.lock, taking care not to commit the modified files.

Is there any current method to override or supplement the restore server when running paket restore, either globally or on a per-group basis?

If not, what would it take to build such a method?

Start at the paket restore entry point and review how paket.dependencies, paket.lock, and paket.local currently determine package sources. Compare the earlier proposal in #1386, then define and validate a global or per-group remote override that supports the remote-developer scenario without requiring committed-file changes.