Jammed stab - refer to post #25. Those constructing terrain clearance paths rely on a little commonsense and awareness of area MORA/MSA whatever you wish to call it. If you are entering an area with an MORA/MSA higher than what you have, don't (IMC) and only with extreme caution VMC. I have no idea how far out an obstacle would be included in the study and JT's post has missed your query.
As guesswork I would suggest that obstacles with a 30nm radius of the field would be looked at, but I cannot see anyone warning crews about the Rockies out of Calgary in the case you cited.