Depending on when you go, there might be a 11:15 show as PP said. We were there this last Saturday and wanted to see what the view from "behind" on Paradise Pier. My Dh talked to a CM who said "sometimes" and there haven't been a lot of sometimes since WOC just started, sometimes if you "hang around' the bridge area, if it's not too full, they will let you stand in the orange area along the bridge which has OK overall views. We were at the CM preview and viewed it from the beginning of the bridge and would say if you are short and have too many small kids to carry, it is an OK option. Better than having people stand in front of you. BUT this is not a guarantee and probably subject to the CMs working that section.
Back to the Paradise Pier view...we stood to the right of the "Wheel of Death" pass the seating area. Viewing between the two large light stands, was just OK. It is what it is, the view from the back. The projections are fuzzy but you do experience some of the 3D effects. Definitely will feel the "heat" and get a good view of the fountain heads. You will not see the orbs that come up from the lagoon. My DH is a tech nerd so he thought it was good to see some of the effects up close although we're still trying to figure out they did some of it. On a Saturday night, it was pretty empty at 11:15. If you aren't able to get a FP, don't want to spend $$, and don't want to wait for long periods, then this view is better than nothing. I would think that if you went to the 9 or 11 showing, you could get a railing view within 30 minutes of the show on most nights. You will get the "flavor" of WOC, but not the full experience and wouldn't want anyone to judge it by it's "back" view. We asked a few of the folks who watched it from "behind" with us what they thought, all them said that it was good, but would really like to see it from the front.