でも、それで士気が下がっては本末転倒ではないかと。

tbd

But, if by that, morale drops wouldn't that defeat the purpose of the exercise?

兵士たちはその歌に士気を鼓舞された。

tbd

The soldiers were animated by the song.

観客側から相手チームをわらってやることは、その士気をくじくことになろう。

tbd

It would demoralize the opposing team to give it the razz from the spectators' side.

If the spectators made fun of the other team, then it would weaken their morale.