Seems kinda silly to me that some would load their gun, rack the slide, pop out the magazine, load another round and then seat the magazine back into the gun.
It would be a little more effort to do it the way you describe. An alternate method, which is the way I use, is simply to manually place a round into the chamber with the slide locked back. Then use the slide release to release the slide, then ensure the safety is on and insert the fully loaded magazine.