However, if you are going to look at end-to-end overall times you'd also need to factor in that cycling time may require time to lock the bike up, shower and get changed. If it's somewhere unfamiliar, I may also need to allow a short time to actually find somewhere suitable to lock the bike up - and that may be a few minutes walk from where I'm actually going. Also, packing whatever stuff I need into cycle panniers takes a bit longer than if I'm going by train and can just use a shoulder bag.
By the way, if it's absolute speed I'm concerned about - the absolute quickest journey times would probably involve cycling to the station and taking by bike with me on the train - although I don't often do that unless I'll be needing the bike anyway, as it's quite a bit of hassle to save, typically, just 5-10 minutes.