Let's consider a home defense scenario.
When you grab the XD from your nightstand or quick-access safe, accidentally hit the rather easy to operate ambi mag catch and then point it and pull the trigger, what happens?
The XD fires. Once. You've just dropped its magazine. I hope you have carpet or the full mag has probably just puked its rounds out after the baseplate flew off.
The 1911A1 fires because it doesn't barf its magazines from accidental touches to either side of the weapon, it's magazine is much more positively locked in than is the XDs. Furthermore, you've trained yourself to sweep off the thumb safety as you present the weapon to the target because you
like to practice with it. It has become second nature and yes, when cocked and locked, it will remain just like you left it.
You want to check to make sure a round is chambered, without taking your eyes away from a potential threat, and/or in the dark.
With the XD you can. With the 1911 you don't have to. If you cocked it, it's because you chambered a round or fired a round. If the slide is locked back, you can't feel the hammer, or ejection port, or any other slide reference point you want to pick. You don't need a swinging metal doohickey on the top of the chamber or another thingamajig sticking out of the back of the slide. Chamber checks are much more necessary on striker designs.
You want to insert the magazine, but you are 1/4" off because you're looking ahead, not at the butt of your gun.
The XD magazine goes in. The 1911 magazine does too, you've just choked it up near the feed lips to guide it and then slammed it home, it's all in the practice.
You have fired 9 rounds. With the XD you keep firing, with the 1911A1 you reload and look at the bad guy bleed out from nine COM hits.
These are not just my feelings. Compete with the two guns, for real, not just having fun at the range.
I chucked the XD and kept the 1911A1s.