Thanks for the replies. Good to hear that the issue is not in my imagination. It's obvous that it's just the way these things are designed, possibly exacerbated by the fact that I'm using a road derailleur instead of a MTB derailleur. I do have a Deore RD that I'll take a look at just for grins.

A agree that my loop is too short as it is and shortening it would make it even worse for the "straight into the derailleur" criterion. I don't really care about aesthetics to get the proper loop, it's just that it's so big it gets floppy and in the way unless I zip tie it to the rack leg. So it's really better function (less floppiness) that I'm looking for (a proper loop with less length).

I get comments all the time about the loop on my other road bike that has a Sram Red RD - the loops on those things really need to be quite a bit bigger than a Shimano RD, at least based on my experience and the installation instructions.

I'm going to try zip tying the cable housing to the seat stay an inch or so below the seat stay cable stop and then cut the housing length to make a straight run into the derailleur. I also think I have an extra noodle or two laying around that I might try.

But, I might try a rollamajig just because I haven't bought a new gizmo lately....

Thanks all.