I also do a lot - correct that - have done a lot of log homes, and the two logs over the lintel openings is OK as long as composite action is not relied upon.
Check the deflection based on the sum of the I's for the two logs. There is obviously a limit to this working for any span length based on the diameter and grade of the logs. This limit should be handled in the structural and framing notes.
Mike McCann
MMC Engineering