In a small space like a 4x4, doing scrog will definitely give you more yield but it has to be done properly. First you have to get the right amount of plants going in the veg room. If you have 3 flower tents and 1 veg space, I would use one of the flower spaces to get set up and going so that you can create the overlap necessary to get the timing down. But you also need to have well known strains that are 9week flower strains to run the 3 cycles or else they will ball up on you.
What you have to do is get 10-12 plants going in veg first. Then when they are ready to go, you take 10-12 cuttings and put in cloner, then set the first set in the flower space and cover with the screen(and keep the lights on 24hrs for another week or 2 before switching to 12/12). keep the others in veg and cut them back significantly. This will slow them down so that they will hold for another 3 weeks. They should "bush up" considerably in that 3 weeks. At the end of that first 3 weeks, remove the rooted cuttings from cloner and set in medium in permanent pots. Then take cuttings from the mature plants and set in cloner, and put the mature plants in their flowering tent and cover with screen. Leave lights on 24hr for 1-2wks to allow them to fill the screen like the first set. Then flip to 12/12.
After setting the second set of plants into the flower space, You will have one set of cuttings in the cloner and another set of clones in medium, in veg space. In another 3 weeks, the cuttings will be rooted and will need to go into pots of medium, and the clones will be mature enough to set into the third flower tent (after taking cuttings from them and putting into the cloner). In 3 weeks, you will do the same operation, but before you can set the next set of mature clones into the next flowering tent, you will have to harvest the #1 tent and prep that tent for the next set. From this point on you will be working your arse off to maintain this 3week rotation and harvesting a tent every 3 weeks. :-)