Hmmm.
If this angel method requires a critical mass then Christianity is in trouble.
Since a large percentage have believed that Christ was returning in every generation, but weren't sufficient in mass to initiate it, it would seem that the notable decrease in Christianity and the sudden rise in Atheism in those born after 1977 would lead away from any possibility of such a critical mass being achieved.
So it looks like the belief in angels, Christ, and God have will shortly be insufficient to wish them into existence even if such a thing were possible.