I apologize if I offended anyone, but I'm just stating my opinion on the Holy Fire. First of all the people attending are not holding one candle, they are holding thirty or thirty three candles tied together and that creates quite a flame. One can even say the greatest miracle is that the church hasn't caught on fire.
Now if I was God and as brilliant as God, and I wanted to affirm the Resurrection to a disbelieving populace, what better way to accomplish it than with a Holy Fire passing the light of the Resurrection to the world? Even if Christians didn't need this affirmation of their beliefs, it does destroy the Muslim belief that Christ did not die on the Cross and that He wasn't the Son of God, as well as the pagan beliefs of reincarnation that is so rampant today.
As for miracles perse, I'm totally indifferent to them, (and believe me I have seen many), since our mere existence is the greatest of miracles. I also believe in the satanic power of magic, so when something occurs it really should be judged it by the fruit it bears. I do know of one American working in Israel that happened by chance to attend the Holy Fire service at the Church and because of it became an Orthodox nun. That to me is good fruit.
Anyway as far as the light appearing on lanterns and people candles at the same time that it appears on the Holy Sepulcher, that is something that is said by people attending the service. One has to take their word for it which shouldn't be too difficult, since it was the words as well as as the miracles of the saints that spread Christianity to a pagan world.