Read above the post from clearwater, which is not about a theory, but about the real life experience. I doubt you have tried the horseshoe already (I do plan to try that soon), your gas mask/shoulder bag carrying experience does not count, as that is exactly what can be called "comparing apples and oranges".
Now then, that is not a very productive, let alone polite way of having a conversation. I tend to refrain from commenting on gear, methods and techniques that I have no experience with. Maybe you should do the same. Given that you have no experience with a bedroll pack (by your own admission), why not at least give it a good try first before extolling its supposed virtues publicly?
Also, a lot of bulky stuff (like a kettle, pot, shovel, flask, hatchet, steel helmet, gas mask bag... was carried outside of the pack or horseshoe, either attached to them or to the belt for convenience of access.
IME a quick way of telling if somebody is an experienced outdoorsman is by the amount of gear strapped to one's belt and pack. The more stuff clipped, tied and otherwise attached to the pack externally, the better the odds that person is a greenhorn (for lack of a better word).
IME again, carrying your stuff securely inside a pack or bag of some kind means there's much less risk of losing or damaging your gear. It allows you to move faster and negotiate difficult terrain more easily. In a military setting, what does a bunch of pots and tools dangling all over the place do for noise discipline?
Anyway, I'm a hiker and outdoorsman, not a Civil War or Red Army reenactor. I'm sure Grant's army had a good reason for using bedrolls back in the day, as did the Red Army with their winter coats 70 years ago - maybe to a large extent because other/better gear was not available in the first place?
I find it curious though that the famed bedroll has all but disappeared from the armed forces in general. Backpacks are issued to the troops in every modern army that I know of. I can't recall the last time I saw someone use a bedroll in the field. Not even as a makeshift bulletproof vest. Maybe it's the quality of wool these days, I guess they just don't make it as resistant to bullets any more?
As for this ultralight stuff - now you've done it, I had to go through my gear and do a quick comparison on my kitchen scale. Metric, just to be a little more "scientific" in our approach.
Swiss army wool blanket (200x140 cm) - 2.2 kg
Ferrino 3-season sleeping bag w/ waterproof carrying bag - 0.6 kg
Sleeping bag liner - 0.1 kg
Yugoslav army canvas backpack - 0.35 kg (very compact and lightweight)
British issue gas mask bag - 0.2 kg
Austrian army 25L assault backpack - 1.3 kg (much sturdier than the Yugo assault pack)
So what does that tell us? Among other things, my sleeping bag weighs about one third of a single wool blanket. I don't have a greatcoat at hand, but the ones I've had a chance to play with must've weighed a lot more than a simple wool blanket. Probably in the range of 4 kg, maybe more (and even more if wet). So much for ultralight camping...
This is not at all to say that the bedroll concept is worthless in my book, just that it's gotten way out of hand ever since guys like Dave Canterbury began advocating the idea again - also making a good buck in the process, because they have a product to sell. Caveat emptor...
I try to keep an open mind when it comes to trying different sorts of gear. I love tradition, but at the same time I'm not buying the idea that "old" equals "good" (or even "superior") all the time. Like it or not, we have many more options available than our ancestors. Which is a good thing.
Heck, I'm sure Alexander the Great and his troops would've loved Goretex boots, 155mm howitzers and radio. In all probability, Christopher Columbus would've killed for a working GPS receiver and a quality compass (hopefully something better than a Chinese knock-off from the dollar store)...
Bedrolls and greatcoats have had their day, too. Nowadays though, we have many more options to choose from, some arguably better and more practical.
YMMV (wow, I think I need to put that in my signature!)