Example: I have two identical MIDI clips, one after the other. The synth is being sent to a bus with a delay on it. I only want the delay to affect certain notes of the clips, so I create an envelope to automate the send level. It works perfectly for the first clip, so I copy and paste the envelope by selecting the whole thing (with snap set to 1/2 notes so no possibility of error), hitting CTRL-C to copy, then moving the cursor to the start of the 2nd clip and hitting CTRL-V to paste it. 
 
Result? The clip is pasted and looks exactly the same as the first one. Everything's lined up the same way. However, some of the delayed notes from the 2nd clip are getting choked, as if the envelope that I copy pasted is a few ticks off. How can this be? Sure the result should be accurate to the nearest tick, and the delay from the two clips should sound exactly the same.
 
Next I try the same thing, but this time I use "copy special" and "paste special." The pasted envelope looks exactly the same as my first attempt, but the timing sounds better. However it's still not perfect - a couple of the notes have an audible click on them which suggests that the send automation isn't exactly lined up with the MIDI notes. But why would copy special and paste special end up with a better result (if still not perfect)? 
 
Has anyone else had any problems with this? I guess I never really noticed it until I tried automating the send to a delay bus. 
 
 

Additional info: I tried redrawing the part of the envelope that was causing the choked notes, exactly the same way as I drew the original (drag-selecting the portion of the envelope I want to raise/lower, and moving that section up or down with the smart tool) - and it fixed the problem. To me that proves that the copy/paste of the envelope did not result in identical envelopes. 

Landmarks and magnetic snapping turned off? It would make sense that snap-to-zero would not apply on a midi-only track. However, when setting the cursor to the starts of those clips, it is subject to the snap parameters of the whole project, not of any particular track. You would want to make sure that it snaps exactly to the clip boundary if your envelope requires tick-accurate placement. Zooming in after cursor placement would be a good way to verify the tick-accuracy.

Well Aim Assist gives me the exact position when I place the cursor, and it was exactly on the bar. I always have snap set to extreme, landmarks off.

Zoom in before paste?

gswitz
Zoom in before paste?

I don't think it's anything related to zoom level. I have my snap set to 1/2 notes, and Aim Assist is giving me the exact position of the cursor.

Just guessing. I know moving sets of nodes can go differently based on zoom level.

No other thoughts.

Are you using jumps or ramps? Post a screenshot and I'll try to mimic. This is the kind of sitch i wish send on/off was automatable.

sharke
Well Aim Assist gives me the exact position when I place the cursor, and it was exactly on the bar. I always have snap set to extreme, landmarks off.

Aim assist only reports the exact cursor position when snap is turned off. Otherwise, it reports what the "snap to" position would be.
 
Aim assist won't help you with snap turned on for pasting envelopes.
 
You need to be 100% accurate both selecting and pasting with automation, and it will paste exactly where you paste it.
 
I tested copy and paste of automation extensively, in Audio/Midi tracks AND Busses when X3 came out.
You can copy/paste envelopes between track types AND Busses, and I can reproduct 100% accurate results every time.
 
The only 2 things I can think of are;
1) Some inaccuracy of cursor placement in either the Copy operation, Paste operation, or placement of the clips.
2) Some snap option - like snap to Zero Crossing, an audio track only need be in view for this to have affect.
 
 
I assume from your description the envelope is on the Synth Audio trac, for the send level ?.
I copy / paste envelopes a lot and the only time they're out of place is when I put them there :-)
 
Probably not much help to you, other than to say that yes, copy and paste of envelopes is 100% accurate. But doesn't mean it's not easy to get it wrong.
 
Cheers - Cliff

Sharke, I wanted to clarify something quick. When you copied/pasted special, did you verify the M:B:T for the paste? I have always considered this to be "tried and true" but your post is concerning me now.