As far as sorting out the panic, you can set aside the locust, which wouldn't share diseases with roses, certainly not RRD. Also the various distorted blooms don't sound like cause for concern if the stems and leaves are more or less normal. Aloha makes a lot of funky blooms.

I haven't heard of wilting tips being an RRD symptom. Possibly the gallica shoot had a tip borer in it or was broken or chewed at the base. When one cane wilts, I look it over very carefully for physical damage.

Extra rain and cool temps would account for extra growth in roses, and bad Aloha flowers.

As for Piccolo Pete, I guess we need a picture. Watch the lowest leaves on the stems and see if they are maturing into normal leaves.

First lets talk about your gallicas.
Whatever was wrong has died. That's good. And what's left seems to be healthy. That's also good.
Some plants get a disease, and the disease is isolated by
quick death of the infected plant parts. A gallica in Madisonville IN died in a very similar way about five or six years ago and it is very close to where RRD had become entrenched in a state park.
I've seen similar quick death in Cl. Old Blush and on my found rose Cleveland Cemetery White. On both Old Blush and CCW, there were witches' brooms of new growth, then the whole stems died. And left behind some plant parts that came back healthy.
Can we say that these had definite RRD? No. But they had enough RRD symptoms to strongly suggest RRD.
Hearing about your gallicas sounds a lot like what happened in Madisonville.

The Powdery Mildew...sometimes when it would appear in a normal summer on a usually PM-unsusceptible plant, the PM would be followed by RRD. This year, that doesn't seem to be the case, in my garden, at least, as my big PM infected plants seem to be putting out normal regrowth.

BUT, my plants aren't doing the hyperthorny " Very red, extra thorny, kind of twisted down on top - or wilted, or something. I looked at it for a long time. There are several of these shoots on one branch." That's at least five symptoms of RRD on that one cane. Can you cut that cane off really low (better yet pull off the roots that support it?)
re the bristly locust....I've never heard of that plant in any of the plant pathology literature I've read. I'll check it next time I go to the library. I think, though, you may have gotten lucky and had a few isolated roots left behind that didn't get the problem into them. I'll see if I can find out what it's causal agent is. I plan to go to the library this weekend.

ALoha's vegetative growth is sort of normal for Aloha. This year, especially, there've been lots of reports of the vegetative growth extending into summer. The only two blooms I've got on Aloha right now are on the top of the arbor so I can't see if mine are normal now or not.

Hope this starts to help.
Ann

Yes. This does help a lot. Thanks to both of you for your input. Ann, thanks for your diligence in researching this. I'm sure I speak for a lot of people when I say we appreciate it immensely.

A little about robinia hispida - it used to be used ornamentally, but apparently has gotten a terrible (but unfounded in my experience) reputation for being invasive, so it's hard to get ahold of unless you locate it wild. Mine was the last plant of an old stand from my childhood home. It was small and weak, under a black walnut, and I guess I overkilled the rescue effort. Anyway, that's what I thought at the time. I do hope you find out something on it. It's a great plant that should be more widely used.

I went out and took some photos, but I can't figure out how to post them. I see instructions on how to post to the gallery and hortiplex, but not on the regular forum. Can anyone direct me to the instructions on this? The pics aren't that great, but I'd love to get your opinion on them.
Thanks again.

You can post on the gallery and link over here, or go to Photobucket and follow their instructions. Copy the html from below your image on Photobucket and paste it into your message here.

If not and you are sure these are aberrant shoots, you should follow Ann's advice to remove the cane at the ground immediately. If this is a 3-year old plant, you know what the growth is supposed to look like. If it is new, sometimes people are alarmed when a rose makes its first normally strong growwth.

I couldn't find any studies of Robinia hispida's potential for diseases' the world seems more worried about its move into coal mine tailings.
But I did find some info on the apparently closely related Black Locust.
I actually knew this from other RRD stuff. Dr. Chapman at Georgetown U. was the first person to do and publish photomicrographs by transmission electron microscope of phytoplasmas of Black Locust. He had Black Locusts with witches' broom and wanted to see the cause, which were smaller than microscopes could show. Thus the photomicrographs. More recently he supervised a Senior Thesis at Georgetown in which his student looked at a leaf of New Dawn with RRD in photographs taken with an transmission electrom microscope and found the virus-like structures that are thought to cause RRD. I've visited Dr. Chapman and he told me he didn't see any of the phytoplasmas in the New Dawn leaves. And he WOULD be the one person who would really know what they look like at that magnification.
So...it seems the two diseases are unrelated, because it sounds as if your locust shares the disease of its closely related Black Locust.
I could be totally off base, but from what I've read and learned so far, the above is my educated interpretation.
Ann

I finally got my dh to help me post these. They are not very good photos, but I think you can see how totally blood-red and strange this new growth is.

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I couldn't remove the entire cane, because there is really only one multibranching cane to this 2yr. own-root plant. So, I removed the affected branch down to about 2 cm from the main cane. I know this is probably real hillbilly of me, but I dipped the remaining stub in chlorox. Couldn't think what else to do. It looks nice and dried up today. The new growth on the rest of the plant is much smaller and pea-green with light red margins. It looks ok so far.

Let me know what you think, and I'll comment on Ann's last post in another post. BTW, please excuse my unmulched ground there. I just put that plant in about two weekends ago, and still haven't gotten around to mulching yet.