The worst part about it is the uncertainty. I've not travelled that route, but the catch -22 is that even if an operator offers bike reservations, if there's no space when you try to get on, you'll have to wait for the next one and hope there's space. That doesn't help when you have to make a connection somewhere along the route. Then there's the issue of "but you don't have a reservation, sir!" As
@Ming the Merciless suggests, you know where you are if you board at the train's starting point rather than an intermediate station. An open ticket with an operator who doesn't do bike reservations gives you more flexibility. Try to travel at off peak times. If a train is quiet you might be able to cram your bike on even if the official spaces are taken. It's the luck of the draw whether you get a jobsworth or someone more accommodating in charge of the train.
If you are a regular bike/train traveller you might find yourself going down the Brompton route. Not ideal if you want to go mountain biking at your destination but I've tried train travel with a Brompton and it takes away all that stress and uncertainty. It's just luggage when folded.
If we had a (much more bike friendly) national standard among operators instead of the fragmented system we now have, at least we'd know what to expect. It helps if you're a natural blagger but it shouldn't be such a trial to just be a passenger with a bike.
It helps to be aware of the possible drawbacks and what could go wrong but you can dwell too much on the doom and gloom of things. I don't take a bike on a train that often but when I have, apart from minor hiccups it has worked out OK. It's a good feeling when it all comes together.
Once you have travelled a route a few times, you might find it less daunting.
