That's what we call a humblebrag. As for that centimeter, that'd be like saying the sound in your home theater becomes drastically different if you move your chair back a foot. Sorry. No. Not on giant over-ear cans.
But moving along. I have a fairly discerning ear and actually spent an agonizing amount of time with three sets of pads on the Pandoras: the stock, the cheap DT770 pads, and the official DT770 pads. The difference being, in order, that the cheap pads added some distance and the official pads had a thicker foam layer. I pulled up my usual battery of tunes, picking out minute details and going back and forth, eyes closed in a dark room, aiming to see what I was losing. I was CONVINCED that having a slightly thicker foam layer was going to mask and veil the sound terribly, because there was no way the waves could transmit cleanly through it the way they would through the nigh-nonexistent spandex material.
The result: bupkis.
The acoustic properties of a driver are not affected by a small layer of material in front of them nor by a minuscule bit of distance on the part of the listener. Now obviously when you slap on the Alpha Dog pads you're creating a vastly different enclosure (which is what we're doing here, it's like a speaker box) as well as changing the angle, but that's a different matter altogether. Naturally, it'll be slightly louder when you're slightly closer, but that's all. Now, it's entirely within the realm of possibility that you just can't get over the mental hump of this and so your brain is just saying "No this HAS to be better" and there you go, but this is no different than the flim flam of giant cables and FLAC files.
So no, don't go around telling people they're sacrificing sound by putting on a more comfortable pad, because that's simply not the case.