The same problem happens at Frankfurt-Fulda too, occasionally. The fast train platforms at Frankfurt are just barely long enough to accommodate a full ICE1 or two ICE3 for example. You have to get very cozy with the buffer stop to get the whole train in completely. The AI often doesn't, leading to situations like the one you described Perhaps the stopping points for the AI (or for Frankfurt Hbf in general) need to be looked into?
