Round pads for 0402's. Is it feasible?

While investigating a routing study for a new bga device, I found the vendor used round 20 mil pads on 0402 decoupling caps.This allows fitting the caps between break out vias on their 1mm pitch BGA. Round pad gives about 8 mils diagonally from pin to via pad versus less then 4 mils for our current square pad (Assuming 20 mil via pad.). This is the only way I see to meet design requirements for decoupling on each pin. Does anyone have any experience using circular pad for 0402 resistors and capacitors?

reply »