If you're warping to zero on any celestial object your target is precisely the same point. This is why you were decloaked - even if you're coming from different directions you're still going to land at the same place because the gate entry in your overview represents a specific x,y,z coordinate in the game space. Not relatively close - PRECISELY the same point.
To manage this, stealth bomber protocol (or any stealth gang, but stealth bombers are most common) is to never warp to zero because it will decloak everyone. Usually one bomber will warp on grid (to a pre-made safe spot off the gate, for instance) and everyone else will (leaving from the same celestial, eg a planet) warp to 10km increments off the target. This places everyone in a beautiful line behind the first bomber, making it easy to line up bombing runs.
Drag bubbles work because you place them along a common axis of travel. Lets say you have a system with 2 gates in it. Imagine drawing a line between those two gates - that's the path your ship will take when it warps to zero from one gate to the other. Dropping a drag bubble near one gate (but a bit off it) will intersect that path and pull you out of warp. In this case, the angle IS important. Even though you're warping to zero, your path has to intersect the drag bubble. If you warp to another planet and then warp to the gate, your path won't intersect the bubble anymore (provided that planet didn't happen to be precisely on a line between the two gates, but that's essentially never the case) so you won't get pulled out of warp.
