Not likely, fairly stock 350 doing some towing and highway driving. The explanation in that video about venting the extra fluid from the dual feed made sense so wanted to check.. Thanks for the info.
Hmmm...That may or may not have been a complete explanation, if that is all the content creator mentiond. The direct drum turns at thousands of RPMs relative to the engine when the trans is driving through it when in first or second gear. So any fluid under the direct piston will push the piston forward causing the direct clutch to drag/partially apply, esp just before the 1-2 shift.
This is not a concern for stock to mild/moderate performance vehicles/applications as the excess fluid never creates enough force to overcome the return springs. High rate return springs can be added to further prevent drag in moderate applications but even those wont be sufficient in seriously high rpm/power situations. The addl .050 hole lends a helping hand to the high rate springs by opening up another exhaust circuit to bleed off that excess fluid, preventing clutch drag or centrifugal apply.
So to answer your question, no - you dont need that extra bleed hole.