For anyone who hasn't seen the clip it's a DSP Delusional Classic.
Phil, do you know how to swim?
"It's been a LOOONG time since I tried." Translation: No, I cannot swim. I never learned.
"Peole are buoyant though right? You float at waist level." Translation: Swimming is easy, it's impossible to drown.
"I could figure it out pretty quick." Translation: Though I have always failed the 1 or 2 times I tried I could totally master it in seconds.
He describes swimming as what it looks like in GTA: San Andreas.
He says if you T-pose in the water and don't move you automatically float, people only drown because they panic and move around. Also being fat makes you sink in the water. Phil says obviously these rules don't apply if you're in a river or the water is moving

Timestamped @ 21m25s, swimming talk ends @ 23m03s with some hoof chewing in between.