I'm still unsure on this but I believe it is correct. Consider biphenyl - a bond between aromatic atoms is not always aromatic. We could perhaps say then a bond between aromatic atoms that is in a ring is aromatic but then consider biphenylene?
In your example it is the outer envelope ring that is aromatic and that fused bond is always single. Another example is azulene. I'm send also to the mailing list as this probably needs some discussion. John
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