Reverse delay trouble

A readers question to the DelayDude:

For a new song, I used a chord sequence recorded with a reverse delay. I think, in my own case this is an appropriate substitute for an extensive synth sound.
But I recognized that it is pretty hard to control the reverse delay and now, I am not able to reproduce my record exactly. I have the feeling that it does whatever it wants to do. Somehow, the rhythm of the reverse signal varies each time.
I am not sure, if this is problem only occurs in my setup but I tried my best to describe the trouble.
At the moment I am using the reverse delay of the Boss ME-80, might this be the source of error?

DelayDude:

The problem is, that in contrast to a “common” delay, the reverse delay does not simply replay the played signal. It rather records a loop in a certain length constantly and replays it reversed and therefore can be imagined as a very short tape looper (played reversed).
Thus, it is so complicated to reproduce the recorded sound. If you start playing at the beginning of the loop, you will get other delay sounds as if you start playing in the middle of the loop. Unfortunately, the respective position of the loop is not visible.
But you can proceed cautiously by playing one tone and then pay attention to the period of time it takes until the “reversed” delay will be replayed. By using the same preset that you have used for your initial record, you could get closer to the solution.
If you have already changed the adjustment of the preset, it might become pretty complicated. But for you have recorded the song, you can replay it as a sonic reference a thousand times.
Provided that you have changed the delay pedal that you have used to create the reverse delay, I think, it will become impossible to reproduce the sound because every reverse delay has its very own style.
In an ideal world, you would have used a plugin for recording. They are triggered in the recording program and thereby always provide the same starting point of the loop.
Short and sweet: difficult but not impossible.
Have fun in experimenting!