Ah, social roles and expectations.
They differ between our peers and our bosses. We expect peers to mimic us, to some extent; it demonstrates agreement. However, we tend to expect bosses to be formal and 'above' us; we don't expect them to empathize or mirror us at all. When they do, it throws us for a loop.
Subverting social expectations isn't necessarily a bad thing; those expectations are simply the shortcuts that we use to evaluate one another at first glance. Creepy people innately give us the willies because we're wired to think that it's a good general rule of thumb; figuring out who to trust and who to avoid has been pretty important in our development.
I'm surprised that the author of this article doesn't mention classic psychopaths and killers who were successful because they were known as charismatic and friendly--exceptions to the rule; they weren't expected to be killers.