question about inoculating your shroomies

ok i was jw if you inoculated your jars with 2 different strains what would they cross breed or what

this has been highly debated; but from what i understand, one strain usually takes over... i only say usually because i do recall reading from a respected member at shroomery that he had seen a cake with 2 separate strains on it??? i dunno, but most people will say that one will take over