Hi, I am using FCP X nowadays, but have seen the same behaviour in Media Composer and Premiere Pro. I have recently edited a small theatre performance, where I have done to more complex edits for two pieces inside it and then have done the entire performance in one camera angle with the two pieces inside. Since the camera used was quite noisy, I had to apply the Neat Noise Removal plugin (wonderful piece of software) and that took quite long to render the 60 minute long sequence. But as I wanted to change the last 60 seconds and switch to a new camera, I made a cut at 59 minutes and changed the angle and FCP X now has to render the whole first 59 minutes of noise removed footage again. WHY? This is crazy. I sent feedback to Apple, but they will never answer my confusion. Do any of you have a technical answer why an NLE has to render an already rendered clip again just because 1% or 99% of it gets cut away?