The simplicity of this argument belies the complexity of what actually happens. The automatic adoption of a specific alignment by an electron is the consequence of a hugely complicated game of three dimensional snooker. In other words, collision mechanics rules. The gravitons of the gravitonstream collide with the gravitons of the electrosphere with resulting exchanges of spinspeed which ultimately result in the electron reorientating itself.

There is another factor at work in the reorientating of an electron - its shape. The shape of an electron results from the different shapes of its quarks: the centrifugal quark is roughly spherical and the axial quark roughly ovoid. The quarks are bound together, as with standing one coin on its edge on the face of another, with the southpole of the oval quark fixed to the equator of the spherical quark and the two then enveloped by the electrosphere. The result is a particle that is roughly conical. This affects the orientation of the electron just as a cone suspended in a stream of water is affected - the "sharp end" turns to face into the oncoming stream.

Interestingly, reorientating the electron doesn't change its direction. If an electron is crossing a gravitonstream, its northpole will move around to face the oncoming stream but the electron will not waver unduly from its course. This applies en masse as well. If large numbers of electrons are within a gravitonstream, they will all have their northpoles facing the oncoming gravitonstream, no matter in what direction they are moving. 

Also, interestingly, being within a gravitonstream doesn't alter the speed of the electron. It might be expected that battering an electron with the gravitons of a gravitonstream would accelerate or decelerate it, depending on which direction it was going relative to the gravitonstream. This, however, doesn't take account of the mechanism that enables a stable electron to maintain its mass and energy at a constant measure. Any mass and energy the electron absorbs from the gravitonstream is matched by an equivalent measure of mass and energy being ejected. Consequently, the speed of the electron doesn't change (although, of course, the speed can be altered by the gravitypull of nearby objects).