I have in fact seen the via trick used for 50mil pitch BGAs, but cannot remember where. I even vaguely recollect some board where that was used for CGA, which s

I have in fact seen the via trick used for 50mil pitch BGAs, but cannot remember where. I even vaguely recollect some board where that was used for CGA, which seems like really ridiculous idea (you don't use CGA packages and then invent some weird kludge pseudo-process).