I am making philosophical inquries on these terms, "real talent" and "level playing field".
If you level out everything, the only difference then is the exact genetic makeup. So just scan the subjects, determine physiological parameters like max Vo2, FTP, etc. and you have the result.
What this does is really exactly the opposite - it only maximizes the influence of factors totally out of control of an individual (genetics) and minimizes the action potential (what subjects can really do to improve).
For me, as an engineer, a "playing field" consists of primarily clear rules and goals, and not so much of various limitations on where to innovate.
Competition is by definition an arms race. Denying it does not make things better.
I think rules are there to minimize health issues and to enable "fair play", but I don't see a clear line between things that are coloquially marked as "dope" and things that are viewed as "nutrition", "training methods" etc.
"Performance enhancing" definitiely does not constitute a line of any kind, since all one does with preparation is trying to enhance performance.
Besides a list of banned things, as a rule, I don't really see any other way. And what isn't on the list is not banned, therefore does not constitute "doping".
These are my personal views. I am eager to hear arguments to clarify or modify them; but so far I haven't heard any.
Understood, however, you have a strange moral compass riddled with causistry. What's not banned is not doping, as Hinault once said, only if you live in world without "values" or understanding of what doping is. Dottore Conconi knew full well he was doping Moser with EPO at the 84 Mexico City hour record, even if the powerful performance enhancing drug was unknown at the time.
Philosophically speaking sport ideally should be about genetics over pharmachalogy and tech advantage (which, within the market construct, can't be regulated). The latter aspects have today distorted the playing field to such a degree that it's impossible to determine real values on the road. This has become so evident in modern sport, as the human factor becomes only one variable in the equasion, rendering it impossible to know how much genetics actually determines excellence.
Add in the economic factor necessary to gain full access to the sophisticated means of performance enhancement and we have entered the Matrix of sport, where alternative realities are fabricated to take the place of reality itself. This is why I scoff at performances backed by petrol dollars with a dubious management running the operation.
Scanning the subjects has been advocated, but has only lead to a biopassport that shifts attention away from pure values, allowing for acceptable discrepancies within a "controlled" doping regime. Within that regime, however, there are a wide range of performance benefits among riders, based on program and response, that cancels the effectiveness of the biopassport itself among riders with adequite medical support. This too costs a lot of money.
Nutrition is one thing and a legitimate means to maximize performance, but we all know this is just a requirement today for doping to achieve maximum effect. Unless you believe riders can eradicate the records of known past doped riders, who incidentally already were guided by nutritionists, as if powerful performance enhancing drugs never existed. Take Pantani and Armstrong, for example. Anyone, of course, is free to believe what they choose. I choose to accept that what we see is a distortion and then try to identify what seems tolerable and what becomes merely obscene.