Yes, nothing to see that morning. Just a guy carrying a three foot long bag shaped like a rifle on the morning that the President was going to drive by his building in an open car. After making an unusual trip the night before. Frazier had grounds to be concerned that public opinion might blame him for not being more vigilant with what was going on that morning. So his story is just a couple of good ole boys driving along in silence barely noticing each other.
Monday-morning quarterback syndrome. Easy to say what Buell should have done, after the fact. Coulda, shoulda, woulda.
Oswald lucked out in being around warehouse workers (especially a none-too-bright Buell Frazier and a mental JackD), not people trained to watch for suspicious activities like someone carrying a long narrow package (in a way so as to minimize its profile, IMO) on the day that Kennedy would be driven around, wide-open to all comers... eventually going from sitting duck to dead duck in short order.