Sword deflection glitch

The Sword Deflection Glitch is a glitch in Halo 3 multiplayer, where if timed right, a Shotgun wielder can block a sword wielder's lunge. This commonly occurs in Infection games like Save One Bullet, as energy swords are more commonly found, but can occur in all gametypes.

Walkthrough
Designate a player with a Shotgun (Player A), and the other with an Energy Sword (Player B). Both players must have shields.
 * 1) Have Player A and B face each other, just in range of Player B ' s sword lunge.
 * 2) Next, have Player A aim a high, so that Player B ' s head is in the bottom half of A ' s reticule.
 * 3) Have Player A shoot. If B dies without any effect or if some of the B ' s shields remain, then Player A is not aiming high enough. A must find the height in which the shotgun will deplete B ' s shields, yet will leave Player B alive.
 * 4) After the correct height has been found and both players have full shields, have B lunge at the same time A shot-melees.
 * 5) If timed correctly, Player B should die, and Player A will lose their shields.

Explanation
It is most likely that Bungie intended it to be possible to parry with over weapons but they ditched the idea because of time crisis but some of it was left in the code, this is a more likely possibility because it has become possible to parry with other weapons other than the energy sword in Halo: Reach. There are a number of outcomes:
 * Player B should die and Player A remains alive and gets a Bulltrue.
 * B should lose their shields and A dies.

Usually, the Energy Sword is an instant kill against any enemy, except when parrying, in which both players will lose some of their shield.