DaasYochid: Actually, from aveilus you can bring the “rayah” at just the opposite: That , in aveilus, the gemoro says that always we go after the “meikel”. WHY? because it is better (odif) to be meikel. Same reasoning as “koach deheteira odif”. ,except by aveilus, we ALWAYS pasken like the meikel, not ncesseraly the case in other parts of halocho.
You are twisting words when you say that “koach deheteirah odif” deso not mean “kulo odif”. As a matter of fact, it is an even stronger statement- preferring the one who is “meikel”. And Pesochim 74B clearly shows the preference of the gemoro to be “meikel”.
You are welocme to continue in your illusion that halocho requires chumros. It does not and this can be proven from a multitude of piskei halocho.