Merging clips

Has anyone else had an issure where you do some fill in recording to fix a mistake and you find that the clip you just recorded merged itself with the original?
 
So, the old clip is there and you cut away the part you want to fix.
Record the fix clip.
Split the clip where you need to.
Delete the unneeded part and the original clip goes away with it.
 
Sometimes slip editing works and sometimes it doesn't. I should note that I record two tracks at once. Usually one with either clean or distortion (guitar) and one direct.
 
Maybe a take lane problem.
 
I have to say that I'm not really impressed with the take lanes. Although, I never really used the layers though. I like the automation lanes though.

  Yep, sounds like you are using "replace" instead of "blend".

I appreciate the replies but I forgot to mention that it does it some of the time, not all the time. A lot of the time it works like it should where I can blend the two clips together to make it sound seemless. It's that few times that drives me bonkers where it won't work like it should.