The first thing you have to remember is that you are NOT being charged with speeding. The prosecution does NOT have to PROVE you were speeding. You are charged with Negligent Driving. RCW 46.61.525 states (in part)
Quote Quoting RCW 46.61.525
(1)(a) A person is guilty of negligent driving in the second degree if, under circumstances not constituting negligent driving in the first degree, he or she operates a motor vehicle in a manner that is both negligent and endangers or is likely to endanger any person or property.
...
(2) For the purposes of this section, "negligent" means the failure to exercise ordinary care, and is the doing of some act that a reasonably careful person would not do under the same or similar circumstances or the failure to do something that a reasonably careful person would do under the same or similar circumstances.
If the officer's notes state that you were doing three times the speed limit, I'd say that qualifies as an "act that a reasonably careful person would not do".

If you're eligible and the court allows it, I'd go for a deferral. In any case, an attorney may be your best bet.

Barry