A flight of Eagles over the Ered Lithui would be pretty dang obvious to Sauron's forces. I imagine the Nazgul with their flying beasts could do some serious damage, and I would think that would put the ring at great risk of falling into the hands of the Nazgul.
Also, the Eagles didn't fly into Mordor until after the Ring had been destroyed, which means the Nazgul wouldn't have been a factor anymore.
The article's conjecture that Eagles could fly undetected over the Ered Lithui grossly underestimates the effectiveness of even a moderately skilled wilderness scout, which I must assume Sauron would have many.
I'm not sure if Tolkien had all this in mind, but considering that Tolkien fought in WWI, which was the first war where air power started to come into its own, I wouldn't be surprised if he took some of this into account.
Also, the Eagles didn't fly into Mordor until after the Ring had been destroyed, which means the Nazgul wouldn't have been a factor anymore.
The article's conjecture that Eagles could fly undetected over the Ered Lithui grossly underestimates the effectiveness of even a moderately skilled wilderness scout, which I must assume Sauron would have many.
I'm not sure if Tolkien had all this in mind, but considering that Tolkien fought in WWI, which was the first war where air power started to come into its own, I wouldn't be surprised if he took some of this into account.