so looking at the chart
If I make a Grasshopepr and a House at these scales, then put them together, wouldn’t the grasshopper be 1/2 the height of the House (grasshopper at 4 house at 10 BU)?
or Grasshopper(4) twice the height of Mark (1.6)?
or oil tanker at 40 the size, wouldn’t it be too large for Mark (1.6 BU) to drive
am I missing something with BU and Size over multiple model scales?
As far as I can tell, it’s a simple way to ensure all of your objects are easy to work with and not have to manipulate a bunch of settings in blender to avoid clipping issues, etc. I can only imagine the scale truly matters when trying to place objects together in a scene, possibly in a 3rd party application like Unity or Unreal.
I haven’t finished this course yet, but I’m guessing if you added the two to a scene you would decrease the scale of the human by 10 or increase the scale of the tanker by 10.
It is basically what Trolly has said.
The concept is to learn how to work on models and scenes in the easiest manner. It also depends on your unit of measurement, but I do like to stick with Blender Units and worry about changing something later.
It would be interesting to put a Grasshopper next to a model of the Earth, but that might not make much contextual sense unless you are viewing the Earth from the Grasshopper’s view with a close-up of the Grasshopper itself.
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@Trolly It is a shame your response was 29 days later and not one day less. It made me think of the movie 28 Days Later 
Have fun with the course, guys~
