Steve,
This is a good, well repeated, not identified by IPC yet issue. I, and some others in industry, for years have proven and recommended smaller pads for various devices. I, and some others in industry, use 0402 pads for 0603 device types. IPC offers guidelines, not standards, as evidenced by the latencey of 7095. No criticism intended of their work. They take time for exerts like you to do the work and inform - through them.
Simply, solder joints are best smaller. Simply, smaller pads and solder paste amounts allow this.
The reason relates primarily to long term reliability as survivabilty of components initially and over time through thermal excursions and those mechanical as shock and stress. It ends solder joint and device end cap cracking.
This all started, and ended, with ceramic chip carriers and other devices so constructed in the late 1970's and early '80's. It's a simple matter of surface TCE (X/Y axis expansion at about 17 ppm/C vs. 5 to 7 or so). It's just taken a time for time to repeat especially with smaller chip device types.
It becomes more critical the smaller you require. It is essential for you to investigate more what many of us have known for years. It just keeps going on.
Earl Moon
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