It's quite simple, there are those willing to carry heavier glass, heavier systems for one extra stop of DoF, and those that don't think it's worth it. Conflicting opinions apparently. But neither side is going to change because of the values of the others, nor should they. Peace will be obtained, when folks stop pimping their photographic preferences as if there are some "facts" that will alter others perceptions of the issue. Facts have nothing to do with it. it's personal preference. It's all about respecting other people's choices.
The obnoxious pimping of one system focusing on it's advantages and ignoring it's disadvantages is by nature confrontational. And what we have here with a bunch of FF proponents (and 4/3 proponents, and NEX proponents etc. etc. ) is the inability to process the fact that many people here, have experience with both systems, and 8x10 view and medium format, and 110 and 6x6 and practically every other type of camera, who will tell you the difference between FF and APS-c in the grand things is relatively insignificant, as is the difference between 4/3 and APS-c. Like almost every other aspect of photography, you need to skip a step for meaningful difference. But that's just my take.
Some folks have a finer sense of "difference". And there's nothing wrong with that, until they assume that others need their guidance on the issue, are somehow less informed than themselves, and start preaching a doctrine to the crowd.
There is nothing wrong with anyone, who decides to shoot only with a Q, 4/3, APS-c , FF and MF or 4x5 scanning back..or any combination there of. It is quite possible for anyone to know everything there is to know about photography and intelligently choose any one of those options, to all of them, and any combination thereof. It's is not up to other to criticize their choice or point out it's limitations.
Criticizing the limitations of others choices is not a sign of intelligence. Believe it or not, there are a great number of us who completely understand the limitations of APS-c, and still choose to use it 90% of the time. I have 6x6 , 645 and 35mm film cameras at my disposal, and access to a very good scanner. We don't need lectures on the benefits of FF. In front of a class, I'd be happy to give lectures on the benefits of FF, and every other system on the planet. It's important that learning photographers understand and explore the options. So, having some impertinent know it all come on hear and constantly harp on the advantages of one system or the other like they are the be all and end all of knowledge about photography is truly annoying.
There is one point in the development of photographers, when they discover for themselves that system that is best for their style. And they may even start to work with that system almost exclusively. I don't mean to temper anyone's enthusiasm. Finding your system is a wonderful thing. But there's no reason to assume that the system that's right for you is right for everybody. And posting pictures and quoting selected facts that support your choice isn't necessary. They will always be lacking for everyone aware of all the facts. Emphasizing some facts, just means you don't value others.
Until you can take joy in your choice while at the same time respecting the choices of others, your knowledge is incomplete, and emotionally, you're immature and confrontational. Supporting one format, doesn't mean you're smarter than anyone else. it just means you've figured out what's good for you. And personally, I think a lot of the push back against formats that aren't your favourite, is the insecurity you have about the choice you're made. Trying to stamp out the niggling little doubts about the absolute utility of one system or another, by converting others to the system, instead of examining your own work and choices.
As a former teacher, I cannot imagine launching into the kind of one sided diatribe favouring one format or another, you see here all the time. When I see one sided propaganda, I often try to present some balance, but I'm not advocating one system or another.
If you were in my class, you'd use every format available in on appropriate assignments. I've had students do narrow DoF on point and shoots. SO when I see people say you have to have FF for narrow DoF, my second year students would be laughing at you. But deciding what camera was best for an individual is an individual decision.
Listen to the one format blow hards if you choose, but balance what they say with a practical understanding of all relevant formats, practical in the sense of using every system and finding out what you resonate with. Listening to the blow hards pushing one format or another on the forum is next to worthless. That's why they have schools for photography. And that's why so many of us who post a lot of images and can enjoy our photography without reference to format etc. stay out of this type of discussion. (I have some personality flaw that keeps me from being able to do that.) It is just so hard to explain to those with extremely narrow points of view, just what they are missing without eliciting one of these diatribes of outrage.
I think a lot of the time, some of the more belligerent format enthusiasts think I stop posting in a thread, because they are right and i am wrong, more often it's just I've grown tired of the insolence, belligerence and ignorance. I'm getting to be too old for this baloney. But over 1000 students went through my High School photography program, the one I built from scratch, and 4 or 5 of them went on to do post secondary work in photography, and many others found jobs in the industry or in related industries, or use photography as part of their duties in other jobs, so I can't be doing anything too wrong.
Sometimes I think those pushing one system over others are like proselytizers seeking religious converts. I hate Jehova's witnesses and format proponents. They are pretty much the same thing. Just show me pictures, and maybe a few examples of pictures you'd like to learn how to take and tell me how much money you have to spend, , and I'll tell you what you need to take them. Prejudging, and saying one system is better than all the others for everything and everyone is for the mentally challenged, who can't see the big picture. And for them, it doesn't matter what you say, they will never understand the big picture.
And I bet 99% of the site doesn't give a crap about this whole issue. They just like the pictures they take and camera they have and might like to learn to do a little bit more, take advantage of a few features they don't know about, gain a bit of incremental knowledge, using the system they have. Some knob coming on with a bunch of FF propaganda is a total geek. We tolerate them, because, it just might happen, that there might actually be one person on the site from time to time, who actually would be a candidate to use an FF camera as their only camera. I have a number of friends who are like that. So having a few people helping beginners understand what FF has to offer, is not such a bad idea. It would be nice if they weren't so damed obnoxious about it.
When hanging out with other photographers, the goal is to assimilate as much of what they know that you don't. Because believe it or not, no matter how much you've learned, others have gotten into niches where they know different stuff that might help you in what you do. A confrontational attitude doesn't help that, neither does a one sided promotion of a specific format.