As most have pointed out a straight ball or a vastly reduced VERY slight hook is THE way to go. (How you choose to throw this straight ball is your choice.) Line your body up using whatever middle range arrow with which you feel most comfortable, 3rd, 4th or 5th are traditional, 4th is most common and throw. The smaller the hook, the less you need to know about the oil pattern or how it has transitioned and less practice balls you need to line up.
For any oil pattern other than a walled up house shot, this is the ONLY safe method to shoot any spare, including any double wood. (Of course you don't need to use a center range arrow for every spare.)
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"...for advice is a dangerous gift, even from the wise to the wise...."
J. R. R. Tolkien