The only problem I see here is that it looks exactly like pyramid-scheme. All the accountability that ChipMixer is proud of - we do not keep your funds, we give private keys immediatly - is missing from this investment idea.
This is exactly what I thought when reading that proposal. I do like it, and it makes perfect sense, but it sounds very dodgy.
It's better to keep an investment-option separate from the mixing part of the site.