That does sound Awesome ngl! Did she leave Manchester Victoria with a Whistle display? Fair enough if not.
When it comes to your point on commuters seeing steam, Terminal commuters will 8/10 times never bat an eyelid at the steam train as they pretty much want to go to A-Z. I remember going to see Tornado many years ago at London Victoria and i remember they pretty much walked past, though some smiled, i was about 1metre back but some of them actually just near deliberately walked into you which did ruin admiring the loco.
However, one of my favorite things about Spotting steam on the mainline is watching people see steam for the first time in decades for many of them. I remember back in June i was at Wandsworth Road station looking out on the footbridge onto the mainline out to Victoria, and there was about 14 other people there to spot Clan line. However when the London Overground train came in under the bridge and people where getting of,f Clan line came through on the adjacent mainline with a loud whistle and was chuffing through with a medium pace roughly 50mph.
Looking round though most of the commuters where just getting out of the station, however, i remember watching many of them staying and watching it pass through and as they didn't expect it, it was great to see them smile and quietly say 'Woah!' and see it haul a rake of pullmans. To many in the community this will barely phase them as its a common railtour, but it was the fact that about roughly 17 more people stopped for 2mins and instead of the 'insert anorak jokes here' glares it was a look of ' i can see why you came out to see that come through!' and appreciated the loco with no prior judgement, it just made it more memorable to me.
But yeah when it comes to terminal trains Flying Scotsman could be in platform 6 with a brightly coloured circus train and many commuters wont bat an eyelid! However, if its unexpected Steam train making its appearance through an average station with chuffs powerful enough that you feel it hit your lungs then yes many will look up in amazement!