strange parameter copy-paste behavior

I has doing pitch deviation editing for my song when i came across an oddity with the copy-paste system for parameters. So when i try to copy and then paste a group of dots in the parameters, they only pasted correctly if they were pasted in an area with no previous dots. When I tried to paste the dots in a previous area with pitch deviations, nothing happened. I initially thought I wasnt copying correct, but it became apparent copying dots only worked correctly if you pasted the new dots into an area with no dots before it. Am I doing something wrong, or is this a legitimate issue with the parameter editor?