Well, my personal take on this everlasting headache of a topic is this:
Ford is a company out to make money. I feel that this "spec" is more an accounting decision than an engineering one. By specing a fluid that only they make, they can VERY easily deny warranty claims, thus boosting profits as warranty claims eat into profits and compound losses. Now, as if that's not enough, they have effectivly forced you to buy the "honey" at $20/quart (cost them at most $4-$5) or run the risk of a warranty denial.
Remember, an engineer calls for a stud, an accountant calls for a bolt. Tally up the number of bolts vs. studs in our drivelines and you can see who is winning the engineer vs. accountant battle. Bottom line is this ... the bottom line is what's most important for Ford and specing "honey" is good for the bottom line.
