Hypersmurf
Moderatarrrrh...
And even if I didn't, it's fairly safe to assume that given that push, pull and slide are all under the one banner of forced movement, that the DM has already adjudicated on slide if he's adjudicated on push.
Given that Push, Pull, and Slide are all under the one banner of forced movement, it's reasonable to assume that a ruling regarding Push will also apply to Slide in similar fashion... and unreasonable to assume that it will not. Except in the specific cases where the rules draw a distinction... which is that Push is restricted to movement away, while Slide has no restriction on direction.
If it said under slide specifically that the attacker causing the sliding effect chooses exactly where the target moves, that absolutely nothing to do with push.
It doesn't say that specifically under Slide. So we're forced to either assume that with Slide (and forced movement in general) the attacker chooses exactly where the target moves; or we're forced to assume that with Slide (and forced movement in general) the target chooses exactly where the target moves.
While one can make arguments that Push permits the target to determine where he moves (subject to the direction restriction - that is, must be away from the attacker), one must also apply the same arguments to the other forms of forced movement... that is, that Slide permits the target to determine where he moves (subject to the direction restriction - that is, any direction at all).
There's no reasonable way to read the rules such that the attacker determines the movement for a Slide, but the target determines the movement for a Push. It's only reasonable to assume that both are adjudicated similarly... and since allowing the target to choose his movement for a Slide is nonsensical, we're left with the attacker choosing the movement for all forms of forced movement.
-Hyp.