Red water just means doing the same thing as everyone else, working on proven methods. Blue water in this case means the first out there selling ERP's.
For instance, a blue market idea would be setting up a mobile ammo shop out where players are farming, and selling them ammo through a container. Selling ammo on the market is red water, selling them in the field is a blue water idea
It's not that field ammo sales would work, but thats the risk you take to reach blue water (less competition), by trying something that may fail instead of just doing what everyone else is doing.
Technically Purgetory is really only limited by how much capital he wants to invest in his production chain and market supply of materials. Having high research makes the game simplier, because you know that by producing things at the end of the tree your going to sell them for a high margin. It's not the only way, its just the easiest.
Just to be perfectly clear, it takes Billions of NIC to complete the tech tree. When you see T4 mining lasers for 10M, it's not because of the material cost, its because of the huge time and capital that was required to achieve the ability to even make them.
As was pointed out, it takes 4 staggered lines to produce T4 items, as well as time and material. The selling price between T1 and T2 is fairly small, but it literally takes 2 times as much time and material to make T2. So, T2 should be at least double the price of T1 PLUS the cost of the prototype PLUS the cost of the kernel research to make the prototype.
T2 for items the drop off npc's just isn't worth producing, it's best to use those to setp to T3, at Triple ++ cost. But now your starting again to limit the market of those capable or willing to spend NIC on T3 items at that expense.
At that point, if you can make T4, your better off doing it, since the T4 will have a higher margin and you've already sunk 3/4 of the capital into the module.
Norgalis is expensive because it is. I know its wierd, players just don't like farming, but ninja raiders like stealing it, and the volume of norgalis off alpha plants is so low compared to incubator cost, you can buy it cheaper. But if it wasn't 'rare' and expensive, the devs would step in and make it so, because that's the point of it, to bottle neck production of tiered items and hmechs.
The trouble with ammo, at least from my production stand point is that there's too many of them, too many locations to sell them at, and they sell too slowly. Which translates to - they take up too many production lines, to cover even one weapon type needs a lot of material (which is NIC captial) that sits around for a long time with little margin.
The new CT base helps a little with tying up production costs, but they still sell very slowly, so given a choice between using material on a slow moving low margin item, or a fast moving high margin item... its a easy decision.
It has only been a few days since the CT change, its highly likely that new producers will start making ammo, because they don't have the choice, so slow moving low margin or nothing is also an easy decision.