I sometimes use shortened dip tubes for this reason, but also because I usually prefer the taste of my beers after they have completely cleared. I still have the naive opinion that my bottled beers taste better...
But a shortened tube may not be a great solution either, depending on how fast you go through a keg. If it takes you awhile to go through a keg, consider that you are leaving all the settled stuff in the keg all that time, and perpetually drawing off a pint right above or through it. Others probablly disagree, but I think this impacts the flavor and clarity, even if you don't move the keg at all.
So now if I know it's going to take me awhile to drink a particular keg, I just leave a full-length tube in there, and drink the first gallon or so quickly to pull it out. It's not unusual for me to be drinking from a keg a year after packaging, and I'd rather get the stuff out of there quickly as it settles.
At this point, I mostly use the shortened dip tubes when I'm doing primary or seconday in a keg.
I've also toyed with the idea of having some sort of floater in a keg, so that I draw off from near the top of the beer. Maybe I should tear apart the toilet basin today and see what I come up with....
Maybe a fishing bobber would be a better idea!