Question about sets of well-orderings

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I recently posted a question on here about sets of well-orders and isomorphisms between well-orders. I have a related question about order-type-comparison: if $W$ is any set of well-orders, doesn't order-type-comparison totally order this set? Even if $W$ is composed entirely of singletons, order-type-comparison still totally orders them, right (considering the fact that every well-order has an order-type)?

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Every well-ordered set is order-isomorphic to an ordinal, and every set of ordinals is well-ordered. So if your set $W$ has at most one representative of each (well-)order-type, it will itself be well-ordered. However, if $W$ contains two sets of the same order-type then comparing order-types won't even partially order $W$, though it will endow it with a preorder.