Metrolink may be extrapolating their theory based on the normal etiquette in that area of track. The NTSB should take it with a grain of salt. They need to look at all the possibilities real hard.
They said they are basing it upon the dispacher recordings and the information gathered from the signal itself (it records the signal’s status when trains go by).
I thought it was spin the first I heard of it on the car radio. Simply, because there was no reason to make a pronouncement like that today.