If you put Anything in cold oil or fat they will soak up more of it. The goal when deep frying is to seal up the outside with a crust and cook the inside without being greasy. That is done by having the correct temp to start and maintaining that temp during cooking.
This is “worng”
The “cold start” lasts for about 2 minutes because the burner is on full blast until the oil just begins boiling.
Raw potatoes are hard and don’t absorb oil.
Burner is then reduced to maintain the slow simmer.
Think of it as a “reverse sear” for potatoes
With the thickness of the wedges I cut, if the oil is at say 350° or browning temperature, the potato will be hard, raw, and uncooked in the middle when golden outside
BTW, the recipe was from a Bon Appetite or a Food and Wine magazine and called “1 Hour Fries”