Perhaps someone would help with this, please.

I held AKxxx Kxx - AKQxx and partner had xx AQxxx KQJxxx -

The bidding (not necessarily correct!) went 1C - 2D - 2S (alpha) - 2N - 3C (iota) - 3D - 3N sign-off

My partner wondered if 1H would have been a better positive response to 1C, but the diamond suit seemed too strong to ignore.  But whichever suit was first bid by responder, the second suit seemingly might be lost.  We started discussing a special scheme for a positive responder who is 55(+), then realised we had soon gone beyond our grasp.

Admittedly this is an unusual hand.  Is there a scheme in OCP after 1C to handle a 55/65 positive responder?

best wishes

Dick