Wow, this was sure similar to my results - remarkably consistent! I agree, 22 is higher than I am used to seeing for a Toyota. But, much like mine, the other wear metals just aren't there.
The difficulty, naturally, would be translating that into real-world terms. How much longer does an engine with 10ppm iron wear last than an engine with 20ppm? I don't know if it's even possible to begin estimating that. I'm sure I'm a lot like the rest of BITOG when I say I would rather see that number as small as possible, even without a specific way to quantify what exact difference that would make.
Assuming that we are dealing with a specific gravity of around 0.95 and 6.4 litres of oil, we are dealing with about 6.1 kilograms of oil. 22 parts per million, at least by weight, would be about 0.1342 grams of iron loading the oil. If we are dealing with parts per million by volume, we would be looking at 0.1408cc of iron or 1.1 grams. That's a lot more, of course.
Of course, some of the iron would end up stuck in the filter and some of it on the bottom of the oil pan and so on - so the actual shedding rate is probably greater than this.
It also looks like the very thin 7.12cSt viscosity seen on my analysis is very similar to the 7.19 and 7.22 you saw on your other two analyses. This is somewhat of a relief, as I was concerned that there was something wrong with my engine that was causing it to be a bad fuel diluter. Guess TGMO is just thin.
The other surprising thing is how different the TBN retention was - with between 8 and 9 thousand kilometres, we now see four analyses suggesting 2.3, 3.5, 3.8 and 4.2 TBN. No idea what that means.