I have observed over many years of watching sports that the team ahead at the half time break is not necessarily a safe bet to be ahead at the end of competition.
Down by a touchdown or more, the losing team comes back with a vengeance to win at the final buzzer. Losing at half time a basketball team will outscore the opposition in the first 5 minutes of the second half and roll to a rousing win.
In general, if you allow your opponent to open too large a lead at half time, you simply won't have enough time to overtake your adversary.
Looking for examples where teams were behind at the half and came back to win the contest, I performed a google of "teams down at the half eventually winning" and got an interesting result collection.
