Question

I saw that the Rabbi said that defining a rabbi as stringent or lenient is a mistake, since every stringency is also a leniency from the other side.
That is of course true, but when people say about a rabbi that he is stringent, usually they mean a rabbi who does not issue a halakhic ruling in accordance with the stringent opinion, but is nevertheless concerned for that view in a case of prohibition. Yet he does not actually establish Jewish law that way.
Example: someone who does not do labor at the end of the Sabbath in accordance with Rabbenu Tam’s view, but brings in the Sabbath in accordance with the view of Rabbi Eliezer of Metz—I suspect there are many such people.
And on that same topic, isn’t this what the Talmud means by: “One who follows the stringencies of Beit Shammai and the stringencies of Beit Hillel is a fool”? It is really grabbing the rope from both ends. Or was the Talmud speaking specifically when Jewish law had already been ruled in accordance with one of them?
(Or as Rabbi Ovadia used to say about the donkey of Rabbi Pinchas ben Yair: “There is a stringent donkey, and there is a donkeyishly stringent person.”)