I don't think you need to be alarmed by any size of bowel movement, unless you don't poop for like three weeks and than lay a two-bowler. That's not a healthy way to be.
I think if you ever have to flush because the toilet's full, you have something wrong with your insides. Might just be a tape worm or a demon, could be some sort of space-time anomaly. More fibre and water should take care of all of that.
I have a personal history of storing poops. I've had long-term inaction followed by multi-layered dumps on more than a few occasions. In case that's confusing, let me elaborate.
(This is the part where you stop reading if you are afraid of poop stories or gross things or vomiting.)
I have taken poops that are three-layered. This means, each individual layer is comprised of a different foodstuff, and has its own texture and color. Imagine, if you will (last chance) a broken-up bran muffin floating in leftover Count Chocula milk, covered by a tube or two of chocolate soft-serve, topped with a spatter of loose buckshot with bits of carrot. That's a real thing.
Short Answer: This is my life. It's not funny!