But that's the entire point - adornments are not part of the lead/follow relationship.
Exactly. Part of the definition of embellishments and adornments is that they do NOT affect the other partner at all. At least, that's the definition everyone I know goes by. Maybe in your community the accepted use of the terms is different, but judging from the replies here, I'd say you and/or your community is using the terms differently from most.
It is possible for a leader to be aware that a follower is doing a specific embellishment and make use of it for his next led move, but that's a different scenario. For instance, if I do a right over left "beat" and quickly unwind to step back on my right while walking, even though I am trying to do it quietly, my partner will sometimes feel it and change his feet to put my backstep into an ocho. This means my little embellishment gets magnified by the fact that it now goes around instead of just straight back.
However, the front beat I did was the embellishment. Doing an ocho afterwards is simply following his lead. His switch to an ocho is simply him changing feet (not embellishing) so that we are on the correct feet for an ocho. Without his quick weight change, we'd still be walking straight back.
Sometimes I think he did this, not for visual effect, but to let me know that my embellishment was not as quiet in my body as it should be. Perhaps he even felt me tip to my left and was trying to save what he thought was a fall. But I still wouldn't call his change of lead an embellishment, even if it built off my embellishment.