Balanced Campaign Scenarios?

[Liebchen]

Anecdotally, there have been statements posted here that campaign scenarios are not really sufficiently tested because it is impractical to test large and long scenarios the required multiple times to make a true assessment. The result is that some campaign scenarios are claimed to be unbalanced and favour one side.
1. Is the consensus that this is true?
2. Across all WDS (Tiller) Operational Campaign game series, and all titles, what campaign scenarios, based on your experieince, do you consider to be the most balanced?

You should make a poll.

I think that the grand daddy of them all, Smolensk '41, is very balanced, fwiw.