Betting on your favourite team doesn't need to be a trap; you just have to be logical, like you explained below. If one can't bet against their favourite team even when the odds are against them, it's better to avoid betting on that game completely than to bet on it and have your decisions based on emotion and not fact.
Does it mean that if my favourite team is not performing well I should be blind to still bet on them to win? you are not ready to make profit if you let the love for the team you support get into your head to the point of not knowing the right thing to do when they play against a better opponent. Manchester United is playing away against Brighton tomorrow S a Manchester United fan the best I can do is to avoid the game cause it's difficult for United to win tomorrow. Avoid any game that puts you in a difficult situation if you can't make good decisions when choosing them .
We are still on the same line; I can't personally make that type of bet, and any fan who allows their love for their favourite team to decide how they place their bet on the game is not yet ready. Betting is not what you follow with emotions; profit is hard to get, but then again we should not be blinded by our emotions and throw our money away just because our team is playing against the next one.