stubble,
No doubt, with good stout 150 grain bullets like a Partition in the 270 WSM, I certainly would not fret if that was my only choice of rifles.
There just are better choices that create a larger margin of error for someone who is time constrained.
So far I have taken elk with a 300 WIN and a 300 RUM and have been present when other elk have been taken with a 300 RUM, and a .270 (regular). My observations are that the bigger guns were more effective. My son killed a large cow with his 270. While the first shot was right behind the shoulder, the cow wasn't impressed. While the elk taken with the other rounds dropped in their tracks with similar hits. His shot did the job but it made for an exciting few minutes !!
Tony.
