Used the dev console to set my crit chance to 100% for testing, hitting enemies doesn't do any more knockback than it usually would. I've attached two videos, the first one being the knockback test with the lance and maxed crit, while the second is at base stats and without the lance.
#Jousting Lance doesn't work
vital ether
I used the test slime because it won't die prematurely and it's easy to knock around, but this applies to any other enemy as well.
celest sparrow
After all the hype up from @vernal rose
vernal rose
naive aurora
Used the dev console to set my crit chance to 100% for testing, hitting enemies ...
Cause dev console disables achievements for that run.
Oh