Could you make Shaco's ability damage adaptive, depending on if he builds AP or AD?

So with the new Runes we have something new that is really smart in my opinion, where abilities change whether you have more bonus AD or bonus AP.

For example Electrocute, the new Thunderlord's, deals "adaptive" damage. This means that if you have more bonus AD it will deal physical damage and if you build more bonus AP it will deal magic damage.

This is really smart because currently on the live servers, it's always unfortunate for AD assassins like Zed that all their lethality and armor penetration won't proc on Thunderlord's because it deals magic damage whereas burst mages like Syndra don't have to worry about that. With the new runes that problem pretty much won't exist anymore.

But why stop there? Runes could be just the start but items and some champion abilities have effects that could benefit from this whole "adaptive" thing aswell.

The prime example for this is Shaco imo. Take a look at his kit: http://leagueoflegends.wikia.com/wiki/Shaco

As you can see, Shaco's abilities deal a mix of physical and magic damage. The problem with this is that this means that it's really hard to balance both AP Shaco and AD Shaco to be around the same strength, one will always be better than the other depending on whether his abilities favour AD or AP Shaco.

For example if you play AD Shaco, your ultimate and your W will deal magic damage which means that all your armor pen and lethality won't apply to that damage whereas if you play AP Shaco, building magic pen isn't really all that efficient either because your E and passive deal physical damage which leaves both builds ( and in my opinion especially AP Shaco ) rather unsatisfied.

On other champions who don't build a lot of penetration having mixed damage is actually a blessing, since it will be hard for tanks to itemize against it, like for example Jax or Shyvana. But since Shaco is more of an Assassin, it is really vital for him to get that flat pen and lethality to reduce the armor of squishy champions to make it easier for him to burst them. Sadly, it's currently unefficient for him to do so because of all his mixed damage.

So why not make his passive, W, E and ult deal "adaptive" damage? This would fix that problem and make it a lot easier to balance Shaco without killing either the AP or the AD version of him. So if you build AP you would be able to build flat magic pen without having to worry about his E and passive dealing physical damage whereas if you build AD you can build a lot of lethality and armor penetration without having to worry too much about your ult and W.

Thoughts?