How common it is to write e.g. $1-o(1)$ for a function that eventually approaches $1$ from below (or eventually equals $1$)? Would a better notation be $1-|o(1)|$ or what is meant is already obvious from $1-o(1)$ ? Obviously, precisely defining everything will work eventually, but I was wondering about the general convention. Similarly, are notations like $|\omega(1)|$ common?
Edit: In other words, would you say "What the hell is this?" is you saw both $1+o(1)$ and $1-o(1)$ in the same sentence, or would you say "Hmm, ok I got it, these are all assumed to be positive"?