When coaching baseball, keep in mind that when learning a physical skill, repetition is the key to making the movements a habit, so working as many repetitions into the practice makes sense. The problem is making sure, as much as you can, that the reps are what you want. Playing catch is no exception and it should be done properly, ALWAYS. Step to the target, catch the ball, and step to throw. Step, catch, step, and throw all in one motion, no extra dancing with the ball. Extra time here will be well spent.
The iBook, Practice Baseball to Win, has this demonstration and many others that can be shown at practice on an iPad.