Have ridden that area fince 1978. Have actually cycled that part of I-10; why? The frontage road had been chip sealed (nasty small size pointy gravel, great for flats) and opted to ride I-10 shoulder (in daylight).
Regards to the frontage road in that area, it is no safer than I-10! In broad daylight on Halloween last year, Kay and I were riding our tandem and got hit at about 45 mph from behind by a pickup truck. Truck stopped 'cause his westcoast mirror got busted and he realized he'd hit 'something.' Turns out the driver was in in his mid-70s,
We were wearing bright orange jerseys and riding on a one-way frontage road on the right side side of road. Driver claims he did not see us!!!
Asked him what did he see; he said, "Well, I try to drive between the lines!"
We were the happiest folks in the emergency room, as we were still alive!
Rudy and Kay/Zona tandem