but I'll still never follow all those PIE connections!

Do you mean you don't follow how gaus, cow, bos, and bous could all be related to one another and how the word they came from was something like reconstructed *gwos? Or, do you not see how Sanskrit, English, Latin, and Greek are all related to one another, though not one of them is descended from another?

Ceci n'est pas un seing.