I may be a bit slow on this, and am not going to be as adament on it as Dave, who has been having this very same arguments for a few years now with many others but:
Doing a simple select * from <tablename> in which the table has no indexes of any kind will perform a table scan, and return the results in the order they are found on the various pages based upon the where clause unless there is a sorting clause to the sql command. Even then, it will perform a table scan, and do the sorting after it has recieved the result set.
When there is a clustered index, then the select will do a index scan on the clustered index and return the records in the order that it finds them based upon the clustered index.
I agree that the way that the engine works can be changed at any time by MS in a SP or a new release, but now you are really stretching into the realm of fantasy. The question had to do with a specific version, and action based upon the current systems and how they work today not in the distant future.
Dave, I guess we will have to agree to disagree on this, as has happened to you many times in the past. (BTW, you can see everything I have demonstrated and said by running showplans against each query.)
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