Ironic thread title! There are plenty Inverness fans who have never had any affiliation for either of that pair.
Your casual reference of supporting Celtic but have changed to ICT suggests too much time interchanging clubs on a PC game - rather than having to literally live out the reality of supporting a wee club like us versus the sickening institution that is Celtic. The religion, bigotry, self-righteousness, and many more unmentionables, make that club one of whom nobody can be proudly associated. There is simply a HUGE cultural divide!
It is inconceivable to me that one day, you support Celtic, but the next, Caley Thistle!
Ouch.....I have to disagree, in my opinion, those fans who once supported other clubs even Celtic and Rangers are just as valued and welcome as fans of ICT as those of us who once stood on the terraces of Kingsmills and Telford Street.
In the days of highland league football, when having a team in the SFL, never mind the top flight, seemed a distant dream, it was not unusual to support a 'big' team. Even when we got into the league there weren't many conflicts of interest between ICT and the big team.
For me, the cup tie at Tynecastle defined the true pecking order. Following from afar, the roar I let out when the second went in told me exactly where my loyalties lay.