i agree with your account of competition as an expression, rather than the essence of crisis tendency. however, if it is, as you say, what has to be explained, what kind of explanation do you give it (historical, aesthetic, economic etc)?
and thanks for your explanation of zero value circulating capital. given that capital depends in a certain way on devalorization for accumulation, tho, doesn't that devalorization depend on the terms of credit, monetary circumstances, inflation, etc.?