I’ve been doing the note input and layout since Dorico’s release that I always meant to read up about various ways of entering cresc and dim and why I would see two < > there … sometimes. I would either use the popover or click the top < > and carry on, not thinking nor caring about it. For a while, all I could think of is that it was some kind of odd preference or key command I was inadvertently doing. If I saw the wording, then I would use those if I needed to. It is not until I actually did need the words … and they were missing that I decided to look into this.
It’s taken a few months to realise what is happening and that the words will still appear regardless! 
Thanks Piano-EK,