Ya, what those folks said. I had itchiness -- ranging from "more than normal" to "holy cow" -- off and on for maybe 3-4 months post-op. Pretty long gone now at 10 months. AFAICT it just happened, and it just stopped happening, not associated with anything else or anything worrisome.
My scar has almost vanished for the top part, but is redder, more raised, and bumpier at the bottom part. Fortunately for me, the more prominent part is recessed between my pecs and buried/camoflaged in curly chest hair, so the whole thing is pretty subtle. I know its there, but I don't have to care. . .