Ok. But Shaas ha’dchak is NOT a kula, it is about finding a LOOPHOLE that just squeaks by, in the event of an emergency. And one could argue, that that is a whole other set of halachos that come under the “In Case Of Emergency” header. Meaning: This and this is the halacha, but ICOE this OTHER thing is the halacha that may be followed if needed (but ONLY because of the emergency involved). Emergencies i.e., pikuach nefesh on Shabbos, often abrogate certain halachos that must ordinarily be followed to the T.
You are mixing up two things. Pikuach nefesh takes precedence over all (but three) prohibitions, even if they are certainly prohibited. Shaas had’chak only allows us to use a lenient approach if there is a reasonable way of understanding the halacha that way.