Here is another site on the Battle of Nagashino 1575.
This site has the new 1,000 gun theory. It appears that this will be the new standard. I do not have a problem with it since there is evidence to support it. The old standard was 3,000 gunners, The Oda army at 30,000 plus, Tokugawa army at 8,000, and the Takeda at 15,000. According to Owada Tetsuo, the numbers are too much. Oda-10,000, Tokugawa-8,000, and the Takeda-6,000. Much more realistic numbers.
Guns still played a tactical and pivotal role in the battle. Nobody is taking that away. The only way the old standard will prevail is if the evidence is found and proven. Can it be changed back? Who knows.
A good book to start is Owada Tetsuo, Sengoku 10 Dai Kassen no Nazo. Please read pp. 110-130.
The site above is in Japanese and useful.
Nobunaga no tame!