bore vs stroke

Some flaws I see in the video...

It's hard to keep torque constant... Longer stroke will give more torque - that's the definition of torque...

Torque would be somewhat constant, even though longer stroke has more multiplying effect over shorter stroke. But smaller bore will have less surface area so less pounds per square inch being applied to the crank to be multiplied.

Torque has more to do with displacement than how that displacement is constructed eg.. bore and stroke.

For power, engines with similar displacement the bigger bore will have more advantage than longer stroke.