Yea you can shave fine. The world won't come to an end. As a matter of fact you could shave with just cold water however I wouldn't recommend that to a rookie. I think patience is a virtue and waiting for the brush and proper soap is the way to go. I think the end result with an experienced shaver would be the same but the comfort is where the real difference lies.

So I said two opposing things here eh? As a rookie you need all the help you can get so without the proper prep you have at least 1 strike against you and for most the first shave is a crummy experience anyway so would the brush and soap change that? maybe yes and maybe no.