The sūtras declaring lup elision need not also be taught, because of the non-currency of the etymological meaning of the words supposed to be formed by lup elision.,
In explaining certain words, it is a round-about way of going to work to say that there was a suffix after them, which has been rejected, without producing any effect. It is easier to say that the form is what we find it to be, and that its peculiar meaning depends upon usage. Moreover, in many cases, the would-be etymological meaning is not in fact that the current meaning which the word has in ordinary language. It is therefore a useless circumlocution to presuppose the existence of a suffix, to add it to a word, and, then after all, to make it vanish.
Thus वरणाः Varanah is the name of a city. To say that it is derived from वरणाः a kind of tree, because the city is situated near such trees, and the trees gave the name to the city, is a cumbersome process. Because there might be no trees वरणा at all near the town Varana. Let us therefore call words like वरणा, पञ्चाला, &c., as simply proper nouns. Therefore there is no occasion for the application of the Taddhita affixes given in 4.2.69 and 4.2.70 (तस्य निवासः, अदूरभवञ्च) relating to residence and vicinity; much less of rules relating to 'lup' elision contained in 4.2.81 and 4.2.82. (जनपदेलुप्, वरणादिभ्यश्च).,