So here's a question - Why weren't Primitive 'Mechs built during the Succession Wars?
My theory is that Primitive 'Mechs, while easier to produce with less sophisticated materials and technologies require a fairly well developed industrial manufacturing infrastructure in place to be available/worthwhile.
So here's how it works. The Succession Wars ruin whole sectors of the layered industrial manufacturing infrastructure of the various Great Houses. To maintain production of BattleMechs, the remaining manufacturing infrastructure has to realign its pyramid to fit the new scheme. This infrastructure is patchy, thin and extremely limited, but surviving 'Mech factories and foundries have to realign to maintain basic production of standard BattleMechs at pre-existing facilities. The alternative is that these 'Mech factories revert to building Primitive BattleMechs - which seems silly. If you have extremely limited resources, or resources that can not convert (like Corean's Valkyrie Factory) you make the most out of what's available.
This situation changes after the Helm Core restarts redevelopment of the Successor States' industrial manufacturing infrastructure. Not only do military industries expand, but so do civilian industries. As these layered infrastructures grow and begin to overlap (a sign of a healthy manufacturing economy) manufacturing sites/resources that were once limited and directed to specific centers for the production of standard BattleMechs are now represented by dozens or more representations. It's not exactly "excess" industrial manufacturing power, but in effect - is.
When the Jihad starts whacking known BattleMech factories with tactical nukes, the excess in military/civilian industries, which were not directly necessary for the production of BattleMechs could be realigned to produce Primitive machines. Alternatively, the military/civilian industries that are directed to the production of BattleMechs can be capped at their terminal end when their target factory is taken offline - also providing a location to produce Primitive 'Mechs.
To summarize, which out an expansion of the Successor State's industrial and manufacturing base, the reintroduction of production of Primitve BattleMechs would not have occurred and is why no such occurrence took place during the Succession Wars.
Thoughts?