I’m amazed by this thread.
First, the STOLE is the vestment proper to all the ordained. It is worn over the left shoulder and fastened at his side by a Deacon, over the shoulders by a priest (used to be crossed at the chest in the old Mass) and by the Bishop hanging straight down (as priests and Bishops do now). In addition, Bishops wear the pectoral Cross (should be worn under the Chasuble).
The stole is always worn and should be worn under the chasuble or dalmatic. The damatic is the vestment proper to the Deacon - not the stole. The unfortunate practice of wearing just the stole is discouraged clearly in the GIRM and in recent documents on the liturgy. Deacons have worn only the stole for reasons of simplicity or to distinguish themselves from the priest - however people still call us “father” after Mass.
The Dalmatic should be worn at every Mass, and at the other occaisions when it is specified - it cannot be banned or restricted to “transitional” Deacons - there is NO difference in the Sacrament of Holy Orders received by a Deacon, transitional or otherwise.
By the way, a Bishop, who possesses the fullness of Holy Orders, should wear a dalmatic under his Chasuble (it’s a lighter weight, Episcopal dalmatic) though this practive has fallen by the wayside.
I know they are exepnsive - but every Deacon should have some - they don’t need to match exactly - vestments are not a “uniform”, though it always looks nicer when they do.
Deacons are NOT Extraordinary Ministers of the Eucharist. They are ordained and ordinary ministers to distribute Holy Communion at Mass.
Also, by the way, when presiding at a wake or funeral, liturgy of the hours or benediction, a Deacon would wear a stole and cope, as well as use the humeral veil when appropriate.
Amazing that after all these years we are still so poorly informed on the Diaconate.