Yes don't make assumptions. I've been told that. I think we all do most of the time unconsciously.
I've also been told to not touch anything hot, don't bang my head, don't leave my house keys in the house when I close the door. Unfortunately I still do all of these things from time to time.
It seems to me the guys made a snap decision with the best of intentions and due to the glare made an error.
Let's all try and use this as a valuable reminder of how easy it is to be caught out.
Next time I fly into SEA I'll try to remember this incident.
To be honest I'm more concerned about flying the ILS onto the 16s in IMC with VFR ish traffic flashing down my port wing causing TCAS RAs. I also remember Aero Mexico and PSA.
Ironically taxiway T is longer than 16R.