I think this disagreement / misunderstanding is based on the terms used / misused ....

Ratio and gearing are two different things.
Low ratio = High gearing
High ratio = Low gearing

Trev said A low gear ratio will also cause a motor to run hot

When it should perhaps have been written thus ...A low ratio / high gear will also cause a motor to run hot.

and I should have written.

A LOW gear / High ratio ie; 15:1, will load the motor less than a HIGH gear / Low ratio ie 5:1

So we are all saying the same thing but have been using incorrect terminology.