Hmmm I do not know. This is what I thought. I run on several instruments both long and short strategies simultaneously or simply completely different strategies on the same instrument that both trade one and short but as you mention it I think I never actually wittnessned that they were holding positions at the same time of opposite gender but I’m not 100% sure (it might have happened and I missed it). I at least never experienced that one strategy affects the other in any way. I always thought of them like running in a sandbox.
But sure, I might be wrong. Maybe Nicolas knows the answer?