After every major doping scandal in cycling, professional teams say they are going to clean up their act by enforcing a zero-tolerance policy toward doping. They said it after the Festina Affair at the 1998 Tour de France, they said it after Spain’s Operación Puerto police bust in 2006, and they’re saying it again now following the revelations in the U.S. Anti-Doping Agency’s investigation into the U.S. Postal Service team of Lance Armstrong. But, to date, none of those policies has had lasting impact.

The latest team to proclaim zero tolerance for doping, Team Sky, has also posited the most stringent one yet. In an October 15 statement, the team said it was asking “everyone, at every level of the team to sign up to a clear written policy, confirming that they have no past or present involvement in doping.” Sounds good, but is it realistic in a world where the most knowledgeable and experienced directeurs sportifs were racing in the EPO era from the late-1980s?

Sky’s new policy has resulted in the decimation of its management team, with the exit of its three longest-serving sports directors, Bobby Julich, Steven De Jongh and Sean Yates. Julich and De Jongh both admitted to doping in the late-1990s—while Sky’s newest sports director, Servais Knaven, stays with the team despite his being one of the TVM riders, along with De Jongh, who was hauled off by French police for drug testing during the “Festina Affair” Tour of 1998.

As for Yates, who raced on the Motorola team with Armstrong and later worked as the Texan’s directeur sportif at Discovery Channel, he said his exit from Sky was not connected to the new policy, and that he was simply retiring from cycling to focus on his health (he has a heart condition) and family.

While Sky has to replace its top directeurs sportifs, Australia’s Orica-GreenEdge squad also has to recruit a new head coach after it adopted a similar zero-tolerance policy and fired Matt White—who admitted to doping when he was an Armstrong teammate. Both Sky and Orica will have trouble hiring experienced team directors because they are in short supply—particularly ones never involved in doping.

A review of  team directors shows a preponderance of men whose reputations have been marred by doping incidents. Here’s a rundown of the top 10 ProTeams in the current UCI WorldTour rankings:

1) Team Sky: see above

2) Katusha Team: Chief sports director Christian Henn and coach Erik Zabel both admitted to EPO use at Team Telekom in the 1990s, while directeurs sportifs Mario Chiesa, Gennady Mikhaylov and Torsten Schmidt were all involved with teams that had dubious reputations.

3) Liquigas-Cannondale: Sports director Alberto Volpi had a positive test as a rider and colleague Mario Scirea was named in an Italian doping investigation.

4) Omega-Quick Step: Sports directors Brian Holm and Rolf Aldag both admitted to EPO use at Team Telekom, fellow sports director Rik Van Slycke had a positive test and colleague Jo Planckaert was named in a separate doping investigation.

5) Movistar: As a rider, sports director José Luis Arrieta was named in a doping investigation, while team manager Eusebio Unzué has managed several riders who were suspended for doping offenses.

6) Orica-GreenEdge: Besides the dismissed Matt White, sports director Neil Stephens admitted to drug use at Team Festina and Daniele Nardello was implicated in the organized doping ring at Team Telekom.

7) BMC Racing: Team owners Andy Rihs and Jim Ochowicz and chief sports director John Lelangue were all part of the Phonak team when Floyd Landis tested positive at the 2006 Tour. Sports director Max Sciandri was a client of the notorious Italian sports doctor Luigi Cecchini, while new directeur sportif Yvon Ledanois was once coached by the convicted Bernard “Dr. Mabuse” Sainz.

8) Rabobank: New sports director Jeroen Blijlevens was a member of the TVM team that dropped out of the 1998 Tour after a doping raid.

9) Garmin-Sharp: Team manager Jonathan Vaughters admitted in the USADA investigation that he doped in the 1990s, while sports director Johnny Weltz directed the discredited 1998 U.S. Postal team.

10) Astana: New team director Alexander Vinokourov served a two-year suspension for blood doping, and sports director Guido Bontempi was named as a client of the discredited sports doctor Michele Ferrari in a 1990s investigation.

Teams such as BMC, Garmin, Orica and Sky have different levels of zero-tolerance policies, but if they were all as stringent as Sky’s, it’s clear that pro cycling would not be able continue because the sport would lose most of its most qualified team directors. And even such an outspoken non-doper as Tour champ Brad Wiggins has been more than happy to work with sports directors Yates, Julich and De Jongh for the past two years.

Perhaps Team Sky’s policy is simply not workable. That’s what no less a critic than the head of the World-Anti-Doping Agency, David Howman, believes. He told Britain’s Daily Telegraph this week: “Zero tolerance doesn't make much sense in the overall effort to clean up sport. In general we are concerned we are losing those who knew about the doping and what went on, and we want them to feel free to come forward. If they are excluded because of a fear of losing their positions or other draconian processes it will once again lead to the omertà and that's a regrettable loss of opportunity to clean up the sport.”

With the sport in a state of flux right now, it can’t afford to lose its most experienced stewards—even if those officials were once involved in doping. It’s a difficult conundrum to solve, but it’s clear that if any zero-tolerance policy is to succeed it has to be one that is accepted by all the stakeholders, including athletes, team managers, race organizers, sponsors, anti-doping agencies, national cycling federations, and the sport’s governing body, the UCI, along with the cycling media and the fans. And the sooner, the better.

You can follow John on twitter @johnwilcockson