To be honest, I have never been a big fan of attic
mounted antennas. I have always thought that
if you are going to spend money on an antenna,
you should put it where it will do the most good,
which is on the roof.

But according to Ernie Bornn-Gilman's theory of
signal transmision, which states, "If you still
have good signal, well then you still have good
signal." attic mounting, while not being ideal,
might be ok provided you can comply with the Bornn-Gilman
conditions. I would do everything else I could
to make sure I had good signal if I were going
to shove a good antenna into an attic.