eruvin 63

 the fatal consequences of ruling when one's elders are around to inspect.

eruvin 46

letting go of who trumps who in rabbinic top trumps halacha games.

(discussing the principles of whose Rabbinic authority the halacha follows when in dispute, and if there is a dispute between a singular authority vs several authorities. examples are given of rulings in cases of niddah and of mourning mourning. but perhaps they are different and one can rely on the other opinion to individuals in particular circumstances, but not as public rulings.)