Yes it is 0 - the point of leaving it there is so you can comment on it.
I know what you mean by the constants, I use PIC C18 compiler for my job that does that with the peripheral library. It's good for readability and examples given by Microchip, but I find it's harder to debug because the names in the data sheet are different. Things seemed to be solved faster with the (1<<n) notation.
I think that because of the success of the Arduino (which discourages users to write to registers at all), we are going to see more and more of the higher level development tools which moves away from modifying registers directly.