Been shooting the same 870 for over 44 years. My dad bought the 870AP in mid-1950, hunted with it for 9 years, then gave it to me in 1959 on my 10th birthday. In spite of getting old and senile, I can take my gun apart, or put it back to gether in 60 seconds, regardless of the conditions, or situation. While serving in Viet Nam 2 years as a combat photographer, I think I stripped, cleaned, and reassembled my issue 870 even faster. Of course that was over 37 years ago and I was a lot younger!
I can't imagine a shotgun that would be easier to take apart than a Remington 870. If there was one, I'd be afraid it would fall apart by itself when I shot it! But my question is: What's the hurry? I take my 870 apart once at the end of the season to clean the moving parts, receiver, and trigger assembly. I do clean the barrel and bolt face after a day in the field, and put a drop or two of oil on the rails. But when I'm cleaning the gun at the end of the season I want it clean and preserved. I'm not in a race to see if I can do it in a New-York-Minute.
I'm sure anyone, after shooting the same gun for as long as I have, whatever brand or model, would be famaliar enough with it to take it apart and put it back together without having to ponder each step. It's all just a matter of personal perrogative in what we shoot and field strip.
TennSquire