re: The Earth & LEO As Test Bed.
No! It is not the only way to go.
It is the way retards have chosen to go.
If you as an engineer believe there are only single paths to an outcome then...you scare me.
You seriously need to look at the whole picture.
I define my objectives as building a spacefaring society.
This includes science, commerce and an infrastructure that both governments and businesses can use.
I don't want Flags & Footprints at Mars or the Moon again.
But, I also don't want false promises and snake oil being sold.