My favorite bug of the .Net connector is how the entire API supports async operations, but the underlying implementation can't tell two different executions of the same query apart, so it's random whether each call will get their own results or some other ones.

But polluting the poll with unusable connections is just Oracle copying the MS-SQL's thing. The C# recommended coding practices will automatically deal with this. (Not that you would want to follow them, but you may want to look and copy this part.)