Some designers make an effort to maintain a web of soldermask between 
     the solder pads on SMT devices, where pad spacing permits. When the 
     spacing of fine pitch devices preclude the web, it is omitted. I have 
     heard that the webs are used to reduce solder bridging. 
     
     Thinking through this issue, I find webs being used where pad spacing 
     is large enough so as to make solder bridging unlikely, while webs are 
     omitted when the pad spacing is close enough to make solder bridging 
     most likely. 
     
     I am interested in any factual data that supports the reason for, or 
     the value of, soldermask webs.
     
     Thank you in advance for your response.
     
     Jim williams
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