Its helpful in so far as they think a .2 mm inter pin spacing is ok, and mine (in the latest one) is .18mm so may be ok. When we get down this far I don;t know where the limits are ... There seems to be a real lack (or I don't know where to look or what to search for) of information on the 3.5mm package. There are stencils and adapter boards that show up but no foot print examples that I've found and not many ICs (and those are like the Exar, show the package but not a pcb footprint).
Peter