We've done this before. It's doable, but not ideal. The trick is to not plan on spending hardly any time in the room except for sleep. If you're back at the reaort early, find a table by the pool and hang out there because you'll just be cramped and on top of each other in the room. The bathroom situation can be difficult. What worked for us is having two people get up earlier, get ready, then head out to the food court leaving more space for the other two to get ready.
You also might request a room facing a pool so that, in a pinch, if someone really needs to use the bathroom and someone else is in there, there's always a bathroom down by the pool! That might sound extreme, but believe me. When one person in our party had a bout of food poisoning/stomach virus, it was nice to have an extra bathroom nearby!!