Turkey Timing Redux

This is part af a multi post about Thanksgiving:
I
II
III
Breakfast
Lunch
Seattle Brown Out Turkey
Tukey Timing Redux
Sides
Afters

Is a puzzlement:
Fannie Farmer offers a handy table for roasting a turkey that shows an 18 pound bird taking about 7 hours at 325⁰ or around 23.34 minutes to the pound more or less depending.
Joy of Cooking says at 325⁰ a room temperature bird will take about 15 minutes per pound depending on how old, how big, how cold and how fat it is. Bigger takes longer per bird but shorter per pound.
Got that?
So, at 250⁰ a room temperature, youngish, biggish, unsvelte birdie might take less than an hour a pound. Else it might take more.
If you have a thermometer tuck it between the thigh and the body. Don't hit a bone! and wait until it reads 190⁰ . If yours is a high tech bird with one of those flap doodle gizmos, just watch it.
If none of the above you need to depend on your nose, primarily. When it starts smelling really good, take a look. Does the leg wiggle freely in its joint? its done.
Roasting breast downs increases moistness of the meat. But you have to turn the bird over before the end of cooking to brown the top.
Assurance is a mugs game. Pay attention and enjoy the day.
--ml