What rushalaim promotes here since 2010 are examples of the average human approach to etymology, attested since Ancient Greece if not earlier: anything can become anything. In the real life, this does happen from time to time, but the majority of words, when analyzed scientifically, appear to have evolved according to certain sound laws, often pretty strict ones. Slavic languages are quite disciplined phonetically, in the sense that sounds evolve more or less predictably in them (unless, of course, when words from different dialects get mixed, like in Standard Slovak). To demonstrate that the variants with b and v are etymologically related, one has to (1) show that this correspondence is not unique, i. e. that there are instances when other related Slavic words show both b and v, (2) explain why both stages, with boj- and voj-, coexist, (3) eliminate the alleged Indo-European cognates for either variant, i. e. prove that one of them is original and another is secondary.