TITLE: When is every orbit closure uniquely ergodic?
QUESTION [10 upvotes]: Given a topological dynamical system $(X,T)$ (so that $T$ is a homeomorphism of the compact metric space $X$) and a point $x\in X$ we call the set ${\mathcal O}(x):=\overline{\{T^nx:n\in\mathbb Z\}}$ the orbit closure of $x$.

Question 0: Is there a name for systems with the property that the
  orbit closure of every point is uniquely ergodic (i.e., supports a
  unique invariant measure)?

It is well known that nilsystems have this property but not all distal systems do. 

Question 1: Is it true that if $(X,T)$ and $(Y,S)$ are uniquely
  ergodic, then $(X\times Y,T\times S)$ has the property that every
  orbit closure is uniquely ergodic?
Question 2: What if in addition $(X,T)$ and $(Y,S)$ are distal?

REPLY [5 votes]: I think the two-sided Morse system is a counterexample to both questions the first question. Consider the two points $x^{(1)}=\ldots 0110100110010110\cdot0110100110010110\ldots$
and $x^{(2)}=\ldots 1001011001101001\cdot0110100110010110$. The orbit closure of $(x^{(1)},x^{(2)})$ supports exactly two ergodic invariant measures, the diagonal measure on the Morse system and the anti-diagonal measure.
By the way, I have a paper with Emmanuel Lesigne and Máté Wierdl establishing lots of strange properties of the Morse system (such as for any point, $x=(x^{(1)},x^{(2)},x^{(3)})$ of $M^3$, $x$ is generic for some ergodic invariant measure, but there exist points of $M^4$ that are not generic for any invariant measure).