you could but if they are to young what will happen...( when you fim the top of a plant instead of 1 main top flower you have 2) the trunk/main stem will not be able to support the weight . If you dont grow them too tall , no problem. But fim plants can split in half if not monitored closely toward the end of flowering. So tie the 2 main stems together if you see a sign that the plant want's to split on you or something like that.
Just Imagine the weight on each side of the plant if you grow them too tall anf fim them to young.