When dealing with Consumer communications, it would seem the word "authentic" is viewed as somewhat bogus. And indeed, the concept that KFC should communicate authentically is quite hard to visualise. By which I mean, how can an organisation of thousands of employees have a genuinely authentic voice? It can have Brand Values, Personas and so on but those are no more authentic than their titles suggest.
However, with Business to Business sales and marketing, there are humans involved and everything is a bit different. In B2B marketing, people buy from people and the decision to buy from one organisation rather than another is frequently because the purchaser knows and trusts their contact at the vendor organisation. At this point, it becomes very easy to be authentic; you simply have to be yourself and demonstrate your domain knowledge.
So creating your personal brand within the brand of the firm makes perfect sense so long as the product or service being sold involves humans not machines (or deep fried chicken).