stripping vs. sanding

Location: Maine
Afternoon sun
Wood type: White cedar
Mold/mildew: No
Reason for previous stain failure: Applied Arbor Coat transparent (natural) stain with Clear Coat sealant on new deck (about 300 sq. ft.), after waiting one year for wood to dry. Within one year it was flaking and peeling.

Now I want to remove the water-based Arbor Coat and replace it with a semitransparent oil-based stain, probably TWP 1500. My question has to do with removing the old stain. I tested Benjamin Moore’s Remove product (recommended by the Arbor Coat salesman) on a small 4’x6’ landing, treated with the same failing Arbor Coat stain. Even after two applications (the second one using a stronger concentration) and scrubbing with a stiff brush, about 20% of the stain remains. So it looks like I will have to sand off the rest.

My question is: For the main deck, is it okay if I skip the stripping-and-pressure-washing step and go directly to sanding? What are the pros and cons? Are there any pitfalls I should watch out for?