I wonder if it's just an age thing? My DS did this also and he would come up with EVERY excuse in the book not to go to sleep...he needs water, a different blanket, he's hungry, he needs the light in the hall on, he's too hot, too cold, his socks feel funny...anything, literally ANYTHING he could think of. Or, he would pitch everything in his crib out (his lovely, his soother, blankie) and knowing he can't sleep without any of those things we'd have to go in to retrieve them. Things have gotten better but we still deal with a lot of this even to this day at 31 months.
We've done both GW and WI/WO (which is pretty much what we are at now) and I stand outside his room and just re-assure him until he's quiet and then I leave. With GW I initially stayed with him until he was asleep and then over time made my way to the door, talking to him. Or I'd sit in the rocking chair which is sort of on the other side of the room. Believe me, LOTS of crying and lots of re-assurance but if you are really consistent and can deal with the crying (which many nights I couldn't lol) you will make progress.