SACD/CD functions breaking in separatly?

I have recently purchased a marantz sa-14. Thus far, I am very delighted with both sacd and cd play back. However, I am somewhat puzzled by the fact that both the sacd and cd functions seem to be breaking in independantly. Does anyone have a hypothesis as to why one doesn't complement the other?

I was under the impression that the lasers and there associated electronics also require a burn in. Once they combine the burn in is from either side but the lasers are not the same. I found each side needed 400 + hours to really smooth out.
My understanding also is that the sacd and cd electronics in the unit each have their own lasers. Therefore, each side requiring their own burn-in. I own a Sony SCD-1 and a Sony DVP s9000es and the consensus is 200 hours minimum for burn for regular cd and 200-400 hours burn-in for SACD.
My hypothesis is that this is an expectation effect: You're very conscious of the difference between SACD and CD. In fact, you're probably hyperconscious of it right now, because you're putting this new toy through its paces. In such cases, percieved differences tend to magnify.Just relax and learn to enjoy it!
While Bomarc may ultimately be the most correct, as the other posters have mentioned there are indeed separate laser assemblies for SACD and CD, as well as pcm chips for the CD DAC, and they will break in separately even though the analog stage breaks in no matter whether it's fed a CD or SACD signal.