Sometimes, but not in this instance. I think our 'real' odds of going down should be around 4/1 so 14/1 is ridiculous and any rational person with some winnings from his bet on Iheanacho signing really ought to reinvest.
On a general point, betting against your own team makes far more sense intellectually than betting on them. You're effectively laying off your disappointment and we all know that disappointment is a big part of being a City fan. It could therefore be argued that it is the antithesis of being subversive.