Like many, I prefer to notate my timpani rolls as a trill (as it is unambiguous, unlike repeat slashes). To get the right playback, I set the interval to a perfect unison. Is there a way to automate this with a single custom shortcut? (of course, it would be nice if Dorico defaults to perect unisons for timpani…).
No, but it’s been requested (quite recently) - see https://www.steinberg.net/forums/viewtopic.php?f=246&t=178027&p=946358&hilit=Unison+Trill#p946360
Thanks Leo,
(I do search for these things before posting something, but I find it very difficult to find stuff on this forum. Any tips appreciated to stop me from wasting people’s time!)
Use Google rather than the forum’s own search, as described here. In this case (and many others) I knew what I was looking for, because I had a memory of actively participating in the previous thread 
Jay! “tr p1” in the Ctrl-O popover in the new 3.1.10 release!