I did not see any such artifacts on my CRT monitor.
I did have the flickering pixel problem on my dlp but i found a way to fix it with my TV.
this is what i did
the usr_tdc option helps remove this. the usr_tdc option seem to stretch some pixels in random columns.
if i use the tdc option with the coarse and fine options in my samsung i can get the pic to look perfect.
they have to match up or you will see the flickering.
i have my tvs coarse setting at 831 and the fine setting at 10.(tv menu-setup-pc-)
to get to the usr_tdc option in the xrgb you need to set (option-on)(dtc_typ-user)
then you change the usr_dtc value to what ever number you need to get you video to look right with your display(i set mine to 829)
as i said you need to find a happy medium between your display settings and your xrgb
check this post out i have some pics
http://www.hdtvarcade.com/hdtvforum/viewtopic.php?t=2047&highlight=&sid=dc8139661e7d13f52cea2543b63ab50b