Ah! But Palpatine isn't waving a wand and shouting Expelliamus is he?

If the spells don't hit him, but force him to lose concentration and dodge, then they've helped a bit, haven't they? There's nothing in the rules that states a spell must be cast to hurt the person directly. In the books we've also heard of great things happening to the weather, and bridges collapsing and what not. Don't forget also the big explosions that have been caused by 'lesser' magicians (Wormtail particularly). Voldemort will be at least that powerful, and a lot more - with that power he should be able to cast large blanket spells that affect quite an area. How can Palpatine dodge something that's spread out over a large area and coming straight at him?