To the collective mind....
 
I'm doing drum replacement inX2 Producer, replacing an acoustic side stick snare with a sampled one out of Session Drummer.
The result is two separate MIDI notes, one lying atop the other. It's not consistent, some hits come in as expected, others with the flammed sound. I can hear it, I can see it when I go to Piano Roll view regardless of what sound I'm triggering. Other drum replacement work is fine. Where do you reckon I should start looking? The waveform of what is creating the transient that then triggers MIDI? Again, some of the MIDI notes do not have the double hit, none of the acoustic wave have double hits.
Hmmm
 
PT

How are you doing this, with Audio Snap?
 

I think there is a cal routine called undup which should strip the duplicates, if they are flamming though it may not get them all. You may have to go through and delete a midi hit where ever you hear the flam,  and make sure the remaining note lines up with the original.
 
One approach I've used is to solo and pan the original drum say hard left, and the new replacement, solo and pan hard right. Get the basic volume close. Go through the track and adjust timing and velocities as needed on the new replacement.
 
 

Yes, I'm working in Audio Snap to create the transients for SSD to trigger from.
SixFinger, that's exactly how I check to make sure the transients are in the right spot in time to match the original acoustic signal.
 
Still, the question is why do some sidestick hits produce the flam and others do not?
 
PT

It's been years since I've used AS for drum replacement, how closely do you check the transient markers on the audio track before doing the Copy To MIDI function? When I get double hits with Drumagog it's due to the resolution being to tight.
 
One workaround would be to clone the original track, hit it with a noise gate & make sure only what you want is getting through, then bounce it to another track and apply AS on that audio. 
 
BTW which version of SONAR are you using? If it's X3 I would highly recommend Melodyne over AS for conversion to MIDI.