When the builder grants you a double turn, what you get is a single turn
with two parts, so you extend your current turn and can place two tiles
and go through all the steps twice, but it is a single turn. The Exp. 2
does not allow you to convert this double turn into a triple turn.
If during this double turn you receive an additional extra turn by
activating an "Extra Turn" symbol from the 20th Anniversary Expansion,
your will perform a new turn after the double turn is completed. This
new turn can become a new double turn if you extend the feature with
your builder again.
Note: Other new turns you may receive from other expansions while you are
the active player may also become double turns. Check expansions such as
Mini #2 - The Messengers or the Saint Nicholas Scoring Board.
But I have some major issues with his reply! Most of the second/extra
turn rules are clear that you can only perform each additional move
only once during a single move:
Our house rule should be simple: When we are playing with multiple
expansion that each allow for extra turns, you can only play each extra
turn only one time!
