It is my belief that the mini chum slick created by the motion of the bait is effective in enticing a shark to bite.
 
I like to use the following equipment when going after sharks in the hundred pound weight class.  
 
1)     A ten foot long surf rod with a medium action to assist in setting the hook.  I prefer this setup to shorter broomstick style rods.  What I lose in hook setting capacity is made up for by other equipment changes.  The fight will be longer with this rod for sure but will also be more enjoyable and most importantly more productive.

2)     A spinning reel with a very smooth live bait drag.  With my reels you can set the reel to give off line to indicate a strike and with the flip of a switch engage the drag set properly.  The drag is very important. Unlike most fish sharks can turn their power on and off at a moments notice.  They are truly not caught until they are safely in the boat.

3)     I consider braided line a must for sharks.  It will not stretch as much as monofilament or fluorocarbon lines.  This is helpful in making your hook sets and it steering the shark away form problem areas.  

4)     Wire leaders are of course a must when shark fishing.  Even a very small shark is loaded with a mouthful of daggers that can instantly break even the best of lines.

5)     If you are going to handle a shark you need to invest in a pair of Kevlar gloves to prevent any major incidents.

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