When we know that the Torah speaks that way then it is a valid understanding. In a normal conversation it isn’t necessarily understood automatically. This is why Rashi is telling us that the Torah uses this language, as we find by Aharon, Velo Yamus.
My point with the opposite of Arichus Yamim is that although not having Arichus doesn’t have to mean a Kitzur, it can be used as a hint to Kitzur. On the other hand, the Klallos of Bechukosai are not related to the Brachos and they are many more Psukim longer.