The Amplitude curve-op only supports "post-offset", i.e. addition after amp. multiplication. It would be very useful if one could adjust the offset prior to multiplication also.
Here's a typical case: you have a curve with a low maximum peak (say at 50%), you want to "stretch" the range of the curve to 100%. That is currently not possible without additional preparation, since the clipping of the amplified curve seems to happen before the offset is added.
Another option would be to clip after the offset has been added, but the pre-offset is easier to work with I guess.