Citation needed. And if you aren't planning to sue over software patents, then the author is clearly correct that this is strictly better than BSD/MIT alone.
Seriously? This is basic IP law 101. No license can be implied if there is an explicit license.
I actually started gathering cite lists for you like I normally do, but instead, i'm not going to in this case. If you really want to argue this point, please go to google scholar and spend the 2 minutes it will take to pull up 100 cases on this.
I don't feel it's fair to argue about a thing without taking the very small amount of time to familiarize yourself with it.
If you find cases that say otherwise, awesome, let's talk about it!
Otherwise, this is like arguing about baseball and asking someone to cite rules because you want to argue that swinging at the ball and missing isn't a strike.
"then the author is clearly correct that this is strictly better than BSD/MIT alone."
They actually are not, as the scope of the implied license is much broader than the scope of the explicit grant here.
The grant isn't specifically about software patents, it's about all patents.
The BSD license grants explicit rights to use the software, thereby granting implicit rights to use the patents in the software while using the software as it is intended to be used.
The sentence "redistribution and use in source and binary forms, with or without modification, are permitted" doesn't go away because there is an "additional grant of patent rights".
"If you use software licensed under Facebook's BSD + Patents license, and the author of the software (Facebook) has patented technology in the software (which AFAIK they don't), the author CANNOT sue you."
This is just flat out false, and i'm not sure why you believe this. The termination is broader than the grant. The grant is for patents in a given piece of software, the termination crosses all software.
Concretely: if you use react, and they sue you over patents in notreact, and you countersue, you do not lose your react patent license. They are still welcome to sue you over notreact, there is nothing in this license that will prevent that from happening. It only gave you patent rights to react.
(It also says that if you sue them over notreact, you will lose all patent licenses in all software that use this license, which is why the termination is broader than the grant).
"The BSD + Patents license is strictly better than the regular BSD/MIT licenses. You lose no rights, you may gain some patent protection."
This is also an incorrect legal statement.
Once their is an explicit grant, any implicit grant you would have gotten is extinguished. In this case, the terms of the implied grant were much better for people than the terms of the explicit one. So you are, in fact, losing something