No, until today I have not. However, getting curious about this I have looked at the docs, registered a client and written a Python
program that fetches my activities for a specific time range. The whole implementation took about 10 minutes.
This app is limited to one user, but as far as I understand one can apply at Strava to allow more athletes, and get larger rate limits.
The app uses standard OAuth2 authentication to fetch an access token and then uses Strava's API to get the activities.
I haven't looked at GC's source code to check how it is done there, but the authentication screen looks quite different to me and
my approach requires authentication via a web browser and a callback domain.
So, provided Strava is not trying to deliberately sabotage or fence out GC, this should work quite es well in GC, I believe
(but as I said, I just looked at this a few minutes ago for the first time, so I may miss an important point).
Cheers,
Johann