First of all let me say i was one of the people that was involved in Getting the sword to proc on all mob types ( because it was indeed classic ) So dont hate, I just want things to be correct.
The proc rate on sword of runes seems to be wrong, there are reports all over the place about groups giving pet weapons and pets procing 20-30 times a minute.
This would be correct if it was 2006, when the procrate was added.
Source Lucy :
http://lucy.allakhazam.com/itemhistory.html?id=5319
2006-12-16 11:38 Added procratemod: '289'
What the procrate mod was before is unclear but It was probabally zero. I am currently looking for more information, while I play, so It may take some time, but this needs to be looked at as folks are doing some crazy things because of this huge dps.
Found this as well from casters realm which has a comment:
"Even so, I heard the Sword's effect rarely proc's"
http://web.archive.org/web/200105121...lID=124&Page=2
It was definatally not procing like this on P99.