These fixes you mentioned were to fix Divine Favor causing a crit by using it AFTER a spell was cast.
You can still cast Divine Favor and Holy Light/Flash of Light and immediately follow up with a Holy Shock to get two guaranteed crits on those spells.
https://web.archive.org/web/20060529021949/http://forums.worldofwarcraft.com/thread.aspx?fn=wow-bugs&t=103709&p=1&tmp=1
Using Divine Favor immediately following Flash of Light can cause the spell to crit retroactively. - Future Patch
Here’s that post from 2008 I linked before:
If you have Divine Favor up, begin casting either Flash of Light or Holy Light on the target you are healing. Then as your heal goes off, press Holy Shock. If you do it right, both of your skills will get the Divine Favor buff effect, and both will crit. This works 100% of the time. If you have trouble doing it, you can spam a hotkey for Holy Shock. I find this trick to work great while healing hard hitting bosses.
Because his latency wasn’t good enough and he wasn’t spamming Earth Shock. Spell batching wasn’t changed until 2014, this 100% worked in Vanilla.