See PHI1562. We currently phlog(...) exceptions during Conduit calls to the error log. This came from D817, in August 2011.
At the time, Conduit error handling was all explicit, and logging error conditions was more common. It's now routine for Conduit to simply raise an exception to indicate a bad-but-not-abnormal state (e.g., invalid object identifier, policy exception, type error, etc). This isn't necessarily ideal. But, in practice, the chance that any client wants to adjust behavior for any given failure state is, on average, small, so this is a reasonable behavior almost always.
This was walked back slightly already in D10042.
Given the modern context, simply removing this phlog(...) seems reasonable.