No not exactly. I install the first post then install the second post, take my measurement and make the rail for inbetween then divide it into equal spaces for the spindles and drill the holes for the spindles.
Once I have the top and bottom rail drilled I take the section to the two post that are installed, drill the holes in the post for the top and bottom rails then take one of the post down so the rail can be installed in the post that is still attached then install the second post, working it into it's original position and reattaching it.
On the first job we installed about 8 or 9 post then took a bunch of measurements and made all the rail sections then went over and working from one corner started installing them working around the deck.
On the second deck we took measurements between all the post, made all the sections then jacked the weight off of the post to be able to move them enough to install a section and then replace it and move on to the next one.