These are stout oils, and I suspect that they would meet virtually any gas engine standard. Their makers don't see Euro spec users as a significant target, so the makers don't bother to test them to anything beyond SM, and sometimes not even that.
These oils are marketed toward and intended for OTR diesels primarily, after all. The amount of Delvac, Delo, Rotella or Tection used in cars is probably a miniscule part of the HDEO market. I suspect the only reason the makers even bother with API SL or SM is that many fleet users like to use the same oil in all of their vehicles, not just their trucks.
Viscosity isn't that much of an issue, since 10W-30s and 5W-40s are widely available.
I did find JAG's experience with TDT a little surprising.
I would have expected it to perform better.
Anyway, if I didn't have a stash, and couldn't find killer deals on pax car SM/CF, I'd probably use HDEOs more widely.
I have one in the BMW right now, and it will get one more run of the Tection prior to the car's winter slumber.
I have also used HDEO 15W-40s in both the van and the '97 Accord.
Again, if I had no stash, and had no desire to chase deals, closeouts and MIRs, HDEOs are a great value at their typical everyday prices.
Also, the pax car oils that meet demanding standards are usually either not as cheap or not as widely available (find PP 5W-40 on a shelf anywhere, and while M1 0W-40 is widely available, it cannot be had in the much less costly per quart jugs, for example) than those that merely meet API SM.