IETF posting delays

For IETF mailing lists like this, I would prefer to use my real 
"professional" email address hsantos(_at_)santronics(_dot_)com. However, since it 
often takes over 24 hours or longer, and in cases over the year "lost" 
(never posted), I regularly now use my junk gmail.com alias account 
which is posted on the IETF list "immediately" with a copy sent my 
santronics.com account hosting server and picked up within minutes of 
my next mail reader pop3 poll.
Have others experience similar delays with their accounts? and had to 
use other domains, like gmail.com?
When I first begin to take notice a while back and last year I decided 
to ask the list admin.  He replied shortly and indicated there was no 
moderation. I also asked a few IETF veterans, a WG chair and AD, and 
they all repeated there was no moderation going on.
But I believe I read an IETF person in the list explained delays was 
mostly due to moderation. If so, while I don't see any reason for it, 
I was never given any notice my email would be moderated and I would 
like to ask why my email is being moderated?
Of course, it doesn't make sense because if there was moderation it 
would be on the address and not the "person" since I can post via 
gmail.com.
If not the case, trying to provide the benefit of doubt and seeking a 
logical reason for it, I figured the IETF list/MTA software is using 
some custom outbound queuing/scheduling logic with a higher preference 
for email domain volume, i.e. gmail.com at the top and individual 
domain accounts last in its scheduling logic.  Since gmail.com is a 
popular account used by many in this list, maybe that would explain 
why the MTA sending this out faster than others. I offered this 
logical out reason to the list admin and he wasn't sure of the legacy 
software queuing logic.
Anyway, just trying to figure out why the delays since I can stick 
with my real account and not the gmail.com junk account.
Thanks

--
HLS