And that's just one blunder among many.... the lack of knowledge about where the pivot point must be, despite claims of experience and expertise with flying tails.
There's a looong history of such bad information because of ignorance, from that source.
Some of the bad stuff is humorous, others like this can lead to crashes.
The totally mythical "9 degrees of downthrust on the Me-262 to cure the poor engine out handling" illustrates several problems with information from that source.
First, the "downthrust" didn't exist.
Second, it wouldn't fix the problem.
Third, the idea of it was said to be proper for two completely different configurations, neither of which could benefit in any way and had actually been accepted as fact by the guys with questions about engines.
Fourth, when all this is pointed out beginning with the invisibility of downthrust on the Me-262, the "9 degrees" is said to be "subtle"...
Which points out the obvious unfamiliarity of that source with downthrust in the first place, and what 9 degrees of it would look like on the Me-262 had it existed.
On the humorous side, is the "200 mph control-line speed model" using an motor that could only get past 100 mph by boxing it up and airfreighting it someplace.
As I say, it's mostly a collection of random technical terms and numbers, which when looked at reveal an ignorance of both what they are, what they mean and how they're used.
This is the 'net though, and "free advice" is worth what you've paid for it.