without a doubt he was doping.
he only came back because he got the green light from ferrari that he would be able to dope. i suspected as much at the time and said so here and on other boards. now it has been officially confirmed.
2009 he was doped to the gills, lost a lot of weight very suddenly, and had stellar perfs during the tour coming out of rest days. we also know that he was being protected by the uci.
2010 landis and feds made it tough. however, armstrong's unbelievable improvement from tour of gila itt to 4th in the tour prologue showed that ferrari had prepped him well going into the tour. we now know that he met ferrari just days before the tour which (very importantly) started outside of france.
his perf at the 2010 tour went steadily downhill from the prologue to being not so powerful along the cobbles, to looking strained on the first medium mountain stage, to losing a ton of time on the next day. refill day (that should always be held after some mountains like it was that year) came a little late and he couldn't risk too much with the scrutiny, nor was it worth it by then.
as for hrotha's claim/joke about 1998. Yes, i agree that i think he tried to come back initially without epo. and that led him to leave paris-nice. it was his cynical decision to go back to epo and ferrari in may of that year that lead to the fraud --
though myth had it that it was due to a week in the hills of carolina with bob roll.