Like others have said, doping was common place at Fench teams but as a nation were probably the last to get on the EPO train. The 90s saw a downward spiral in French cycling re teams with Fagor stopping in 89, Toshiba at the end of 91 and RMO pulled the plug in 92. A big chunk of RMO moved to Festina giving them a French feel but according to Willy Voet it wasn't until just before the Tour in 93 that they tried EPO and it was haphazard at first. It was at the start of 94 that they put together the team programme of doping which excluded the New-pros re Bassons/Lefevre/Halgand.
Castorama pulled the plug in 95 and according to the late Philip Gaumont who was at the team, they were still only starting to move with the times in 95 and the same at GAN when he was there in 96. Castorama had a major rep regards Corticosteroids/Hormones and both Gaumont and Laurent Desbiens were both busted in 96 whilst at Gan. Armand De Las Cuevas who was a Ferrari disciple, was team leader in 94/95 but apparently did his own thing with Ferrari. Ironically, Castorama also had Mr Clean, Giles Delion on their books at the same time and he managed to win GP Rennes in 94. Gaumont also won the Tour de Poitou Charentes in 94 which he has said was his last ever clean win.
Strangely enough, the same race was won the following year by a rider who also said he won clean, Nicolas Aubier. This rider turned pro in 93 with GAN and says there was no pressure to dope but it was still happening, he stayed clean the first year, tried a bit the second year but said there was no mention of EPO until he joined Casino in 96 where he was put under pressure to try EPO. He quit the sport. According to Aubier, he never saw Chris Boardman dope whilst at GAN which is mainly where Boardman's 'clean' rep comes from. Two other GAN riders didn't use EPO according to Gaumont, Yvon Ledanois who couldn't handle it and Eddy Seigneur by choice.
Greg LeMond also of GAN team mentioned about they had an idea of what was happening but it wasn't until a team-mate moved to Italy that they got the full picture. This could have been Philipe Casado who moved to AKI in 94 or Eric Boyer who moved to Polti in 95. Both riders quit the sport after one season in Italy, and Casado sadly died during a friendly rugby match. Pascal Lance, another GAN rider was also named as a clean rider whose career had also suffered for refusing to dope according to Giles Delion.
Based on all these accounts, it would seem that the French were very much behind the times. Even at Festina, Willy Voet says it was the influx from PDM that really opened their eyes to proper doping. GAN seem to have been very slow to change and at a guess, by the time they had caught up with the rest, the 50% rule was introduced followed by the Festina affair in 98. When the new French teams arrived in 97, Ldjeux and Cofidis along with the revamped Casino hired a load of overseas riders for success. Rominger, Armstrong, Fondriest, Rebellin, Gianetti, Hamburger, Jaermann, Massi etc.
The introduction of EPO is always an interesting topic but I strongly believe it started with a few individuals in 89/90 before then spreading quickly in Italy 91-93 with other countries following track with the French the slowest to react. By 1994 it was widespread and by 96, it was almost everyone.