Shunters probably did a lot of other things in the old days aswell, and this day and age you must be prepared for all types of work in any position, they call it multiskilling. I know the intermodal boys don't employ trainees and have been told that TO's have the opportunity to progress to trainee drivers in that division if one becomes available. As you suggest Bulk use a different strategy when it comes to drivers and TO's.
What about the Coal division?
*Looks at the 8 off the street trainees in my depot*
Intermodal can and do hire trainees- both internally as second persons and off the street with no prior rail experience.
Under the new recruitment system, regardless of division if you want to apply for higher grade position will need to run the entire recruitment process. The days of the "foot in the door" are rapidly closing, and given how highly competitive the industry is, it is no wonder. As I previously warned- A TO position is not going to make it easier to get a driver's position and it will count as a mark against your name if you move too soon out of the job.
TO's from an Intermodal perspective will give you jack squat experience as to what a driver does or the skills necessary beyond how to align a piece of metal. With the exception of bulk, TO's do the ground work for the other divisions. No depot I am aware of in PN has TO's that drive locomotives yet.
SFT used to offer a program that a TO could progress to driver, but under the new EA as well that progression is gone. All position must be advertised. Merit based selection, whether you hate it or love it, seems to have sunk its teeth well and truly in the industry now days.
As a generic reminder as well, it really isn't that hard to work out who is applying for a position if they have been active on-line in forums such as these. It is known fb, rp etc etc are checked by PN so if you want to give your application a good start- show the right attitude. I saw a thread elsewhere on this forum where someone has clearly burnt their bridges with one company.
Focus your efforts on how your going to get your resume read over the 8000+ applications and how your going to interview. Those first 10 seconds will more often then not decide the outcome of the interview.