We've traveled with our bikes a fair amount and had some excellent experiences getting on and off trains.
Euro Star is a dream with special racks and painless delivery of your bike to a dedicated luggage area. France's TGV system is great with dedicated seats for bikes and cyclists though it is nearly impossible to book bike tickets without going to a train office. We've also had an epically stressful experience on the Thalis from Paris. The Thalis has no space for bikes; your bike must be fully disassembled, placed in a bike bag and stored in a "standard" luggage rack. This isn't so bad, but on occasion Thalis institutes X-Ray screenings; this goes very poorly with a bike in a bag.
We're about to go on a longer trip with MANY transfers and want to know if you all have any tips for getting on, off and on again with minimal pain and suffering. How do you deal with the fact that many european trains have steps that are nearly impossible to navigate with a loaded bike? How do you get all your panniers on and off the train without having them wander away while you are fetching the next load? Do you have any advice for tying Ortlieb style bags together to make things easier?
Any advice you can offer is greatly appreciated!