That's kind of what I'm getting at. Without a rangefinder, it's a big advantage to have a 3000+fps MV (3200 even better). With a rangefinder, you can get great expansion and terminal performance with 2/3 the bullet weight and half the powder charge, out to similar range.
I've actually never owned a .270, but it's been a favorite for a lot of guys in the group I've hunted with a bunch, so I've watched a lot of deer and elk shot with 130 to 150 NBT, accubonds, Barnes, and ELDX and dressed/quartered them afterwards. I don't think those wounds are substantially more or less devastating than I've seen with .22 and .24 cal TMK/ELD bullets (except the hard bonded/mono bullets, generally narrower wound channels and slower deaths).
That's getting into the trajectory and performance profile that we are talking about with the smaller diameter bullets. Again, we can get very similar terminal performance with much less bullet and powder. A 6CM with a 108/109 ELDM does that with ease, and a 6mm ARC doesn't need to be pushed very hard to do something very similar as well.
I count the ELDM, ELDX, and TMK as being all very similar in terms of how they perform terminally from what I've seen personally and what I've seen documented. The "stay together"ness of the ELDX and its importance is in my opinion overstated by Hornady. It would take LOTS of animals shot and very very detailed notes to tease out meaningful differences between those three bullets in like calibers, weights, and impact velocity. A 6.5mm 130 TMK, 140 ELDM and 143 ELDX will all produce very similar wound channels and very similar average distance/time to incapacitation for similar shot placement.
The NBT, by the way, is a good bullet that I've used and enjoyed quite a bit. The 165 was one of my favorite .308 bullets for a while, and the 120 7mm put my son's first few deer on the ground reliably. It's a little harder (especially the 120 7mm) than I've come to prefer, and I think there's some basically "free" improvements to the profile available through the lower drag VLD style bullets (ELD, TMK, Berger if you like the way they work, Accubond LR, etc). These are incremental improvements though, and I definitely think they are more important the smaller you go. The benefit to me from the additional damage done by the softer bullets is that it allows the use of smaller cartridges/bullets, rather than that I think it's needed for the larger stuff. I'd happily use a NBT if I had to shoot a .308 or .270 and knew my shots were going to be under 400.