My understanding is that the Ilford material is identical to the Cibachrome. Ilford bought the company. contrast masking is a almost a requirement for for this process, unless you're printing very low contrast slides. read comments by Christopher Burkett on his website (christopherburkett.com) . He was also featured in a back issue of View Camera magazine.
I also understand that Ilford now has a medium or low contrast version of the product, it helps with the contrast problem, at the expense of "sparkle" and saturation in the printed image.
I think a masking system such as yours would be extremely beneficial to anyone printing "Ilfochrome/Cibachrome".
Although I was very impressed with it, I gave up on Ilfochrome because of the contrast limitations (I couldn't commit to creating an unsharp mask to make a decent print), and the cost. I was shooting 3 bracketed transparencies per exposure and 16x20 Ilfochrome was costing about $10 per sheet.
I now shoot Portra and print on Kodak Endura paper.