I don't necessarily disagree with you, Bill. It might be the best bet.
A lot of it depends on the schedule: where and how long are photo stops and runbys. For the Victorian event with multiple trains, how far are they spaced out?
For the daily train making good time, it's pretty easy to catch them at Big Horn then the curve at MP305. It's
tough (basically impossible) to beat it to Sublette from the curve at MP305, especially if you are hiking down.
A single special train with photo stops might allow you to easily do all of the above plus more. But, again, with multiple trains? I don't know. Staying put might be the hot ticket.