From reading the other threads, I don't think it is applied both ways. I have seen it mentioned as straight forward conversion, so that 50% DI would count as a 100% [(50/50)x100] and 15% SSI would count as 50% [(15/30)x100], because they are based on item max intensities. But I would also like to see some clarification.
The above leads to some confusion regarding the single property intensity caps are that I can imbue. In one of Wilki's posts he mentions 100% SSI, but currently the maximum intensity on crafted/looted items is 30% (ignoring crafting with ash wood). The current cap of total SSI is 60%. What is going to be the limit for properties? If I can exceed caps, wouldn't that be a waste of total intensity to imbue? Sorry to creep this into your topic, my apologies.
Stayin Alive,
BG