In all my last games, going for Philosophy was suicidal. There's just so little you can do with spearsman and archers alone.
That's why you have to be in a good position for it. Neither did I say that you should immediately research Philosophy after Writing.
So here's the thing. Military Theory gives the science necessary for war, at the cost of gold and subsequently, culture. Why not just research Trade afterwards and continue towards Writing? That's exactly what you do. At the cost of gold, because you'll end up relying on expensive horsemen. This will also be at the cost of culture, production, and possibly even luxuries, because of how much later the other techs will be.
Again, why not just research those other techs immediately? You can by ignoring Philosophy. This is an especially important choice because you may have been forced to take cities one way or another. Often times I would end up forced to expand my control of a region to survive on higher difficulties. Now, for the question of why there should be such crippling war when I could just puppet everything? Playing with a lot of civs can be debilitating on higher difficulties if you don't control the available land, due to how the AI is so good at rushing weak points. Authority makes many of these problems irrelevant at the cost of a certain amount of freedom on later choices.
With Writing, you can rely on a combination of spearmen and eventually horsemen once the way towards Philosophy is clear. The nice thing about libraries is the extra science will bring this all about at a faster pace, provided that you have a different source of early game science. This will let you go to war without early gold hits if you get some good trade going with other civs. All in all, if you have some form of self reliance and some good choke points where spearmen can hold out, then Writing is an excellent choice, due to the fact that it can support a proper empire without the early gold hit. It is very difficult to do if you don't have the necessary start for it though.
This was really frustrating to go through because I'm trying to defend rushing a tech...Seriously, VP has a bunch of ways to ignore a lot of this crap without getting crippled. I've had plenty of games where I wouldn't bother with either building until barracks suddenly became the only way to field a large military. Feel free to shoot these arguments down because I'm pretty sure the holes are aplenty since the last time I rushed Writing there was just no way for anyone to beat me. I'm pretty sure I had a damn good pantheon at the time too, so now it's probably entirely dependent on what civ you're playing on. This is what I get for playing Germany on Deity so much...I haven't managed to get some early game freedom in so long...
Anyways, I don't see how Barracks need to be nerfed for the sake of ignoring them. My only problem with them is how insanely important they are with the cap system.