It now appears to me that adding IIR affects the overall distribution of item types in such a way that more currency orbs drop overall, and IIR likely has an affect on the frequency distribution of orb types as well. However, this distribution difference is not anything as straightforward as normal/magic/rare currency orb groupings as I originally thought. My sample size isn't large enough to nail down the actual percentages, but I think the difference is significant enough that adding IIR appears to be a viable strategy to obtain more valuable currency.
As well, from my findings, IIR even improves some other worthwhile drop trends. Most importantly though, I have to pass along my grudging -- but complete -- acceptance that removing bias in this game in order to achieve actual random data -- now that I have attempted it myself -- is extremely and frustratingly difficult to obtain. Read on for all the gory and confusing details.
So, Slipperyjim in this video found that IIR was better than IIQ for making currency, over a very large and impressive sample size. However, there were a few things that bothered me about his methodology that I felt needed to be improved before moving forward with any final conclusions:
1. Strongboxes were included in his results, and while overall the contributions of these will eventually even out, the amount of bias introduced by having one or two more Arcanist strongboxes in one sample set over another is large enough to sway the numbers several percentage points either way. A well rolled Arcanist's in a well rolled map can give as much currency as running 5-7 full maps.
2. Currency from selling 6 sockets was not separate from raw currency drops, which made it difficult to evaluate what was happening overall with orbs as a specific item type. Also, some lower value orb types were not included in the results.
3. The configuration of IIR only was used, and no baseline was set without IIQ and IIR. I feel that having IIQ is a "no brainer" for an experienced POE player, which means that the better test is to understand the value -- if any -- of adding IIR on top of IIQ, while setting a baseline to judge the relative value of both. For more poe tips and tricks, stay tuned to U4GM. You can choose www.u4gm.com where you can poe currency trade cheap.