That's exactly the scenario I fail to imagine. From the start, they are inherently unequal. One has a few years on the other in terms of both age and work experience. There are things that are viewed more leniently in a young kid just starting out vs. someone who has been out for a while, Certain faux pas when writing e-mail, presenting in a meeting or navigating office politics will be forgiven when the person is a 25-year old new grad but not when it's a 30-year old person with 'real' full-time work experience. Kind of, if a 2-year old announces that he went potty all by himself it's a proud moment, if a 22-year old pharmacy student does the same, it's just disturbing.
how your experiences make you a good candidate
Again, if someone has experience that can translate well into a role in industry - why are they seeking a fellowship and not an actual job? What kind of psychological issues do they have? I go in expecting to be a preceptor, not a therapist or a nanny. And if someone failed to acquire any useful skills during time they were out - they are probably a weak candidate anyway.
I get it that a person may have had just the bad luck of being second-best when they applied as a P-4, but if they were truly a good candidate, why didn't they apply all that resourcefulness to finding a job that would get them where they want to be, such as at a consulting firm or even do a residency if they ultimately want to be an MSL? And if they did try and fail at all the other ways, they probably aren't that good and will be outcompeted the next year just as they were outcompeted as a P4. In the scenario that they simply never thought about industry before and they happily worked retail or hospital for a few years and now they decided they want to get out - what do they have to give them an edge over strong P4 candidates? If they had the drive, the motivation, and all the other soft skills that distinguish the superstar candidates from all the second-bests - why are they looking at fellowships vs. all the other ways to join industry?
So again, I am open to the theoretical situation that a 'spherical in vacuum' candidate exists, who has been out and working for a few years and yet is a strong candidate for a fellowship - but I simply cannot come up with a picture what that candidate would look like. The same qualities that would make someone a great fellowship candidate would lead them to not be an a position of applying to fellowships after having been out for a while. Plus, there is the factor of having to compete against a crop of P-4s who are just as smart, enthusiastic, etc. plus they have done everything right.
If you can 'paint the picture' for me, what a strong fellowship candidate who, say, has been out of pharmacy school for five years, would actually look like, I am all ears.
I think the only scenario I can see a non-P4 being a strong fellowship candidate is someone who is currently doing a residency and who decides to go for a clinical or medical fellowship in industry...
A pharmacist who graduated with BS degree
That would mean someone who has been out and working for more than 15 years. Someone like that applying for a fellowship would really make me question their mental health.
Maybe some of the less-popular newer programs may be an option... Every time there are a handful of candidates who are obviously head and shoulders above the rest and everyone wants them, but they will pick the programs they want and the rest will be stuck with their second-bests or even third-bests (some programs may choose to not hire anyone vs. hire a subpar person, but most of the time for political and accounting reasons programs choose to take a candidate even if they are not too enthused about them... been there, done that).