Why Not HOT on I-5?

The area’s radio waves have been filled with announcements about how I-405 commuters will soon be able to enjoy 45 mph speeds between Lynnwood and Bellevue as a result of WSDOT spending $334M to implement HOT lanes between the two.  The WSDOT has already announced plans to spend an additional $1.1B to extend them to Renton. 

The WSDOT justifies these expenditures by claiming they can reduce the congestion for everyone by adjusting HOT tolls up to $10 to maintain the 45 mph on the HOV lanes.  They also increase car pool requirements to +3HOV during peak commute to assure they can do so.  (Apparently there is some regulation requiring they maintain 45 mph on HOV lanes)  Drivers on I-405 who experience "some of the worst traffic in the state" are sorely in need of help.

However, I-405 commuters are not the only ones needing “help”.  A May 8, 2015 Puget Sound Regional Council (PSRC) report to the Eastside Transportation Partnership (ETP) “Stuck in Traffic: 2015 Report” included a chart showing I-5 HOV travel times between Everett and Seattle during peak commute had increased to 75 minutes and 68 minutes for the morning and afternoon commutes.  HOV travel times between Federal Way and Seattle were 55 minutes and ~50 minutes.

By comparison I-405 HOV travel times between Lynnwood and Bellevue were 40 minutes in both directions and Tukwila to Bellevue were both ~33 minutes.   If HOT and +3 car pools benefits are worthy of spending nearly $1.5B on I-405, why don’t they do so on I-5? 

The answer of course is they know it's a fraud. The +3 HOV car pool requirement and the reluctance of commuters to pay the $10 toll means the ~$1.5B the WSDOT will spend on I-405 HOT, like the $3.6B Sound Transit will spend on East Link, will increase not decrease congestion.