What's the probability of stumbling onto a Hamiltonian path?

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Suppose we have a graph $G$, which for sake of convenience we'll require to be vertex-transitive. Then there's a natural notion of a random path: start at any vertex $v_1$ (and this is where the vertex-transitivity is used), and from a vertex $v_i$ choose $v_{i+1}$ with equal probability from all the neighbors of $v_i$ that haven't been visited yet. If $v_i$ has no unchosen neighbors, the path terminates. If $G$ has any Hamiltonian paths, then clearly there is a non-zero probability that a path chosen this way will be Hamiltonian; the question is, what is the probability that it is?

There are a couple of trivial cases: if we have a cycle graph $C_n$ or a complete graph $K_n$ then the probability is clearly $1$. (For $C_n$ once we've made our first choice we have no other choices to make, and for $K_n$ as long as there are unused vertices there's a path from that vertex.) But already for a graph as simple as $D_{2n}$ (two copies of $C_n$ with edges between corresponding nodes) it's not clear to me what the probability is, or even what the asymptotics are.

Has this probability been studied, either for specific graphs $G$ (the Petersen graph immediately springs to mind) or for families of graphs like $D_{2n}$ or $\mathbb{Z}_2^n$? Is there any known characterization of the graphs where a Hamiltonian path will always be found this way? Does anyone have references to similar problems? Many thanks in advance!

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Is there any known characterization of the graphs where a Hamiltonian path will always be found this way?

Chartrand and Kronk called these "randomly traceable graphs" in the paper with the same title (https://doi.org/10.1137/0116056). They completely characterize the possibilities. Aside from $C_n$ and $K_n$, there is only one more case: when $n$ is even, the complete bipartite graph $K_{n/2,n/2}$ is randomly traceable.