If we suspect high interaction/overlap between two experiments we put them in separate cells. Otherwise we allow 2–3 overlaps trusting that even distribution of experiment X across both parts of experiment Y will balance out its impact. BTW this is a question that divides the world of split testing experts. This is a good article on the topic:

https://conversionxl.com/blog/can-you-run-multiple-ab-tests-at-the-same-time/