The Soyuz ship plans to dock with the Station on Monday. Because of the high profile of this mission, and the Russians' need to demonstrate that they have some measure of control, instead of simply taking directives from NASA, they refused to delay the launch by a day or two, to ensure Endeavour's departure. If I could tell you what could go wrong, it probably wouldn't be a problem, but there are just too many unknowns. In addition, astronauts spent the last few days 'tourist-proofing' the station, an unplanned act that all by itself could initiate a critical unexpected problem. And of course, the irony is again that if so much pressure hadn't been centered around Tito's 'mission' then there would be a far less likely chance of disaster than there is with all the minor and major changes taking place at the same time in order to accomodate the mission.
Causality is such a weird thing.
I'm starting to think that the whole concept of causality serves to confuse predictions and understandings of events, whether they are physical, neurological, or social. The article quotes NASA officials who think sending Tito up would be dangerous because he's not sufficiently trained and could endanger himself and others. Well, obviously it wasn't Christa McAuliffe's lack of training that precipitated the Challenger disaster, but it's also fair to say that the disaster wouldn't have happened if she wasn't on the mission. Back on that fateful day in January 1987, a shuttle was launched in far more adverse conditions than ever attempted before. Morton Thiokol, makers of the solid rocket booster that failed, spent the 12 hours before the launch trying to convince NASA officials that the launch in such cold weather wasn't a good idea.