But I do feel that Qui-Gon, sensing he might fail, prepared for the other side in advance, while Maul was held back by the red force-field. It wasn't explicit and could be interpreted in many ways but it was reminiscent of Ben's calm before he disappeared in ANH.
To be honest the whole Qui-Gon discovers the secret of immortality sub-plot isn't too hot. It would be better just to cut it than run rings trying to explain it. (Aah, that's more like it, THX).