should it matter that a team is bringing back a favourite routine ? Even if they have done it before, it's still a very special dance. Some of the moves like the ChAJ or the Turtle lift may no longer be new but they invented them... Their precision should be rewarded too.
I will be blunt, I don't like Lilah and Lewis. I did the first couple season but then, they copied and pasted the same style over and over again and to me, that's even more a sign of lacking innovation.
Piper and Paul do not need to prove that they are innovative. They have done it throughout their entire career.
Also, if the sport really wanted teams to get innovative, they wouldn't have rules about which turns need to be performed when and how and at what speed (for instance in the RD for the speed) ... they would let them explore. Ice dance is by nature, confined in a space where innovation is not really expected that much... so why penalize a team that is brining back an old favourite and giving fans goosebumps?
I am not happy that my two favourite teams both brought back old programs because I like discovering new choreography and finding out the intricate relationship of movement and music in dance... but Piper and Paul (and LaLa) skate their Free Dance so well that they should be rewarded for it.
Composition mark shouldn't be about what is innovative but about the choreography put on the ice that day. Was Piper and Paul's Free dance badly choreographed ? Definitely not. Each element, each movement had its purpose. Everything was polished and refined.