No, for the time being Dorico won’t show a half note by default in that specific combination of rhythms. Dorico will always break notes that cross the half bar, except in particular combinations of short-long-short syncopation patterns; however, if either of the “shorts” in the short-long-short pattern are not a single note, then these rules for syncopations won’t apply. This is something that we plan to add further options for in future versions.
For the time being, you will need to use Force Duration in this kind of situation.
This weirdness, as you call it, is fundamental to Dorico, which treats tied notes as a single note and notates it according to your notation settings. You override those settings by using Force Duration.
The reason for this is when you tie two notes together, they cease being two separate notes, and become one single note all together. The properties and settings of the first note in the tie chain then applies to all subsequent notes it “eats” later on in the tie.
Therefore if the first note doesn’t have its duration forced, subsequent notes take on that state as they get tied.
This is why, in situations where you want specific durations represented within a tie chain, we recommend forcing the duration of all notes, then tie-ing left-to-right along the tie. It’ll produce the cleanest results.