Linear Profiles

Capture One has linear profiles built in, but they are not in Lightroom or ACR. I would find a lesson on linear profiles very useful. Topics that could be covered include: 1) what is a linear profile 2) when would you use them 3) how do you make linear profiles for your camera and finally the part I find the hardest 4) how to make adjustments when using liner profiles. I have tried a linear profile in Lightroom for a photo with lots of highlight detail. The profile worked well but I struggled with getting enough contrast back without destroying the highlight detail I wanted to bring out.