wilderness - 5:05 pm on Aug 22, 2012 (gmt 0)

One more question. Does blocking an IP in two different ways in htaccess cause a problem or does it matter? Like with deny,allow and RewriteCond.

Yes.
In fact, I get some 500 errors (loops) when a page request is caught from some UA and IP duplications requests.

I've no idea of the cause on my end, possibly some inconsistency on my part.
I don't explore resolution because the frequencies are few and the 500 serves the same end result as the 403.

FWIW, I use deny from and SetEnIf in conjunction with similar rules in mod_rewrite, which is generally a no-no.