I’ve done a lot of research into scar care, and I agree with your assessment that the massage you’re doing is helpful, likely more so than the Bio Oil. Bio Oil is OK, but it has vitamin E, which can make scars worse for some people. There are better solutions.
For older scars, polyurethane sheets have been shown to be particularly effective. For more information, see The Complete Guide to Surgery Scar Care at TransGuys.com.