Oh believe me, I know how the black sexlinks work

I've done them on purpose.
And yes, since the rooster was barred and the hens were the ISA Browns, they *should* have all been barred, but they were NOT. So I'm wondering if maybe that specific cross does happen to produce a sexlink of sorts, even though it's not a recognized one.
I ended up with 10 chicks that were yellow with black polka dots and 21 barred chicks. I'm just really curious and don't want to wait to know if there's a chance someone else has done it too.