Are devils worth 7 blood each?

[Soapyfrog]

Soul Contracted Devils are effectively free troops.

They provide you with a mass of highly mobile ratehr strong troops: of course they can be beaten, but so what? More are on the way...

And you are not "stuck" with the strategy... clearly you can be simultaneously clamming, and fetishing, and doing whatever other ridiculously overpowered strategies you might have going for you... except you also have loads of free devils!

So there is no downside... there really isnt any other worthwhile activity for expending your blood except for making some blood thorns, blood stones, summoning up the unique devils, and given the quantity of blood a skilled blood nation can rake in this is quite trivial activity happening alongside your soul contracting operations.