Don’t really want to go too far down any rabbit holes in this case but looking at this again it’s not just the tie that stands out, it’s the suit.
The 11.29am witness - described by BC (page 140) as “a domestic cleaner walking between jobs” - saw an agitated man wearing glasses standing on the corner of Gowan Avenue and Munster Road. This man was said to be wearing
a dark blue pinstriped suit. (Moments later or perhaps even moments before, Jill would’ve driven in to Gowan Avenue from the Munster Road end.)
There were a couple of other sightings in this area, around this time, that tie in with the cleaner’s. Around 11am a motorist saw a man standing between two parked cars at the same Gowan Avenue and Munster Road junction - the motorist also noticed a dark blue Range Rover parked on the corner. And not long after a different witness sees a man, said to be wearing a blue suit, standing similarly, between parked cars further along Gowan Avenue.
Of course the big stumbling block to all of this is that the gunman, as described by Richard Hughes and Geoffrey Upfill-Brown, was said to be wearing a jacket. Could the two neighbours have mistaken a dark jacket for a dark blue suit? I’m not convinced. But then, none of the witnesses who gave ‘partial identifications’ and were relied on at trial mentioned a coat, either, and that didn’t seem to matter to anyone in the end, so perhaps we can gloss over this discrepancy too!