Boondocking in the sand -- how soft is too soft??

I've done a lot of BLM desert driving when we lived in AZ, and would be a lot more worried about high-grounding the trailer as you go in and out of the wash than I would being stuck in the sand.

I won't take a trailer somewhere I haven't scouted first. Drop the trailer if you need to and take a test drive. Ten minutes of hitching up is a lot more fun than three hours of trying to get a grounded trailer to move...