It can't have been, as I have suggested the same thing at an earlier time, too.
so this looks familiar no?
[COLLAPSE="Diddy Dixie Duo Breifing"]The way I see it, two moves would be shared.
Sure Dixie would follow Diddy much like nana follows popo , but notice how the partner has never been an active part in DKC games (Until DKCR Co-op, which is understandable). The partner is shadowed out, meaning that the character doesn't perform unless called upon. This unlike, the IC's who both attack in the same stroke, Nana even acts on her own sometimes.
Without changing anything from the Selection screen, Diddy would remain the leader unless switched through a Down B. In this version, he would sacrifice his neutral special, the peanut popper (which isn't a heavily utilized technique anyhow), for the piggyback move.
Much like Donkey Kong's F-Throw, the combo would be able to toss one another in any direction. However, for recovery purposes, the player's throwing ability would resemble Lucario's recovery where he can "swerve" the direction.
Much like the game, any higher platforms that the partner is thrown will pull the player upwards. As you might imagine, mobility might be more difficult in the piggyback position. Especially if the design of that move takes away the player's ability to use their recovery special.
This would be the only technique that would heavily resemble the IC's, but in Diddy/Dixie's defense, the technique originated from their games.
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In the other manner, such that the player would rather have Diddy's peanut popper and banana's, a player simply would select Diddy (or Dixie) from the character selection menu. This is similar to Zelda/Shiek and the Pokemon Trainer, except without access to the partner (AKA standalone play).
A De-sync may also occur in the unfortunate event that the player 'accidentally' throws their partner off the edge. Certainly the loss of the partner would leave the player without two special moves, so to compensate, the game would return the standalone moveset to the player.
To regain the partner play, the player need only press and hold a move like 'B' after falling off screen, otherwise he/she would retain the standalone play. Imagine they include the DK barrel at the return, as such in KRool Boss battles. The player could ignore it and it will blink away, or they can bust out their partner by pressing 'B'.
The only tedious portion to this style is the event that a player simply wants to startout with a Dixie combo, this could be easily compensated if the player holds a combination of buttons at the start of the match (much in the way that Zero Suit Samus can be accessed from the get go).
*****
There you have it! In the end, we get a new character, Diddy get's a few moveset tweaks (which is not unheard of), and the Combo has its own authentic flare. My favorite thing about all of this is that the DKC memoirs will get their proper representation. Both DK and DKC can be spotted as an important sector of Nintedo's history. [/COLLAPSE]