Thanks for the article. Offhand, I think it may be applicable to badminton too despite no research done on the subject. I'd venture to say, the underdog mentality is more positive than having home soil advantage in most cases.
That said, the likelihood of JOJ upsetting LCW at the semifinals stage is not insignificant - the pressure on Lee CW winning that elusive title is greater whereas JOJ as the underdog (on homes oil as well which may be a positive for him) may rise to the occasion and play above himself. In fact JOJ is known to play rather well against the top players.