System Information
Win7/64, GTX 750 Ti

Blender Version
Broken: 2.74 official

Short description of error
If you copy&paste keyframes of an action that has been converted to an NLA strip that has been shifted in time, the keyframes are not pasted at the current frame but with a frame offset.

Exact steps for others to reproduce the error

1. Open the attached blend file: The keys at frame 80 are selected. The current frame is #120.
2. Copy & paste the keyframes. I expect them to be pasted at the current frame (#120), however, they are pasted at frame #200. This is probably due to the offset of the NLA strip, but this is not a clear usage for the user as editting is done in action space, not NLA strip space.