Arguments from authority are frowned upon in most forms of formal debate, since the purpose of said debate is to argue and build upon facts firsthand - as opposed to merely repeating other people's consideration of those facts. But for the purposes of advocacy and informal discussion, invoking authority is tremendously useful for getting past knee-jerk rejection of new ideas. Most people are quick to bypass anything that they are unfamiliar with; in this information-dense age some sort of filter is needed to keep a focus on important matters, but folk in every era have been reluctant to engage with the new and the unusual.
Thus one of the necessary activities for any growing concern in any field of human endeavor is to convince influential, knowledgeable people to publicly provide their blessing. On the one hand this is all part and parcel of networking: if you're working on a disruptive new approach to aging research, say, then at some point you have to convince a sizable fraction of the existing research community leadership that you are right, and that your approach is indeed better than the established dogma. You need to build a network, and bootstrap your support.
In most cases, great new ideas can be easily discerned in hindsight, but in the early days it's a matter of a hundred rejections for every cautious expression of interest. You have to kick down a lot of doors. No good idea is accepted without a fight - and that is the human condition for you.
The disruptive and vastly better new approaches to aging research and extending human longevity that I favor are (as I'm sure you all know by now) collectively known as SENS: the Strategies for Engineered Negligible Senescence. SENS is is an assembly of tremendously good ideas expressed in the form of detailed research plans for medical biotechnology, and is (to my eyes) enormously better than the sort of work presently undertaken by the mainstream of longevity science. I say this meaning that it will most likely produce better outcomes at far lower cost in time and money. The present mainstream seeks only to slightly slow aging, and is moving glacially and at great expense. SENS aims to achieve rejuvenation of the old, and can be proven to work or not for a fraction of the amount it would take for the mainstream to develop a single drug to safely and modestly slow down aging through metabolic reprogramming.
Needless to say, with SENS being such a great idea and better plan of action, it's been a struggle this past decade to get it to its present level of respect and adoption. No good plan goes unchallenged in this madhouse world of ours. Congratulations should go to the Methuselah Foundation and SENS Research Foundation teams over the years, most of whom have worked tirelessly behind the scenes and for little recognition. The public at large, however, lagging behind some years in following the scientific conversation, remain suspicious of anything that presents itself as SENS does - new ideas, involving only a small portion of the scientific community at first, talking about human longevity, the existence of public scientific debates over validity in past years, and so forth. It's easy for the fellow in the street to knee-jerk and reject, just as he does for any new idea that has yet to take over the mainstream.
This is where the argument from authority is useful and indeed often necessary in the real world give and take of advocacy for a cause. It launches you past the first hurdle of immediate rejection, to a point at which people might actually start to consider factual arguments - i.e. start to give any sort of fair consideration to your position at all. For SENS, the resource of first recourse for the argument from authority is the SENS Research Foundation scientific advisory board. Again, this is not primarily why the advisory board exists: an initiative grows by networking. But it is enormously helpful when in casual discussion or debate for someone like such like myself to be able to point to that advisory board and say "look at these leading scientists in the fields of aging research, genetics, regenerative medicine, cancer research, and others: they have evaluated the scientific merits and goals of SENS and support it."