Many proc weapons which scaled with spellpower on the 2006 client do not retain such behavior in Classic+ which really cripples their already low damage potential. Vengeance not benefiting from bonus spell power similar to a Warlock’s Shadow Mastery affecting both the base damage and additional shadow spell damage. Then you have to consider Blizzard made these changes under the pretense of some things not aligning correctly with their ‘reference client’.
Guide to RECKONING (Unchanged in 1.9!) 10/2/2005 7:05:02 PM PDT
“Normally if you’re sitting down you would not get Reckoning charges from auto-attacks. However, you could gain charges from random NPCs by constantly sitting and standing up due to server lag: mob would try to attack you as your were sitting, so it’d be a forced crit. However, if you stood up just as you were getting hit, the server would see you as if you were standing and get a Reckoning charge.”
“I did find this video from 2006 showing a Ret Paladin with Neretzek, The Blood Drinker, and his weapon scales 100% with spellpower. https://www.youtube.com/watch?v=Pk_kHHI0t4o At 1:34 you can see his Drain Life hits for 571 when the proc on Classic only hits for 141 to 163. I also did some reading through the vanilla patch notes, and there were no mention of any changes to drain life or spellpower scaling.”
The overwhelming evidence and video proof is hilarious but I can understand the feeling of not wanting to watch 2006 era 240p youtube pvp videos.