Just wondering how do you figure that a one piece base is more secure than a two piece base?

The one piece only has three screws holding it to the receiver yet the two piece has four screws attaching them to the receiver. Not to mention that a one piece weighs more which puts more sheer force on the three screws than does the two piece bases.

Another little annoyance is that a one piece base covers up half of the ejection/ loading port and makes loading just a little more dificult for folks with big hands.