I have an intranet site that I'm mirroring overnight while the site is unused. 
The site is a Mediawiki site.

No matter what I do, I cannot get the mirroring speed as high as I want.  I
have disabled the security switch, increased the socket count setting, and
increased the maximum transfer rate.

I've done a lot of test cases, and in every case there's never been more than
3 established TCP connections (nowhere near the 30 I've tried requesting).

Here's an example where I mirrored a very small subset of the site:
Mirror launched on Wed, 08 Oct 2014 00:04:32 by HTTrack Website
Copier/3.48-19+htsswf+htsjava [XR&CO'2014]
httrack.exe <url> -w -r2 -O <paths> -%N0 -c30 -A50000000 -%c500 -%P0 -j0 -s2
-%A standard -F Extract -v -#L10000000 -%! -B -*/Special:* -*/User:* -*/Talk:*
-*/*_talk:* -*/index.php?*

Result:
HTTrack Website Copier/3.48-19 mirror complete in 3 minutes 22 seconds : 361
links scanned, 359 files written (21100443 bytes overall) [5261561 bytes
received at 26047 bytes/sec], 21090198 bytes transferred using HTTP
compression in 358 files, ratio 23%, 41.6 requests per connection

What am I doing incorrectly?  Thank you!