Is it possible for Stack Exchange to make available $\LaTeX$ abbreviations for \mathrm{E}, \mathrm{Var}, \mathrm{Cov} (possibly with new commands \E, \Var and \Cov)? The problem is that things like $\mathrm{Var}[X\mid Y]$ look much better than $Var[X\mid Y]$, but we end up loosing a lot of time typing that.