When you make your initial attack run on your opponent is it better to go into a 90 degree zoom climb or keep it shallower.
As FLS said, you zoom to avoid getting shot and reset your advantage. But the angle depends (as most ACM questions do) largely on what the opponent is doing. Some examples:
Did the con make and continue a (i.e. 180-degree) flat break turn ? If so, a shallower turn (high yo-yo) might be advisable to quickly re-position yourself above and behind them, in order to press the attack.
Did the con make a flat S-break (back into you after the initial break turn)? In this case you may go almost straight vertical to re-position yourself above the con (and quickly drop back in via something like a wingover).
Did the con make a vertical S-break (similar to what Latrobe uses in his film above) to go for a shot on the overshoot? If so, a sharper vertical zoom is advisable with some off-angle to get out of plane of the shot solution, perhaps using a spiral climb (to potentially rope an aggressive con and/or get back behind their 3/9 line).
As you can see, the "correct" move is almost always dependent upon what the opponent is doing.
The most commonly made mistake I see from most BnZ attackers is climbing in a direction away from the con. This often creates too much horizontal separation which simply gives the defender time to regain E prior to the next attack.
The key to BnZ is to maintain vertical separation after each pass (zoom climb, maintaining E advantage) WHILE
avoiding excessive horizontal separation (staying above them, maintaining positional advantage). The correct zoom climb angle is whatever allows you to do both of these -- which is
relative to how the con is maneuvering.
Hope this helps.
<S>
Ryno