Can you just drop any line with two commas that are adjacent or separated only by whitespace? Something like:

 $ cat data2
example aaaa,bbbb,cccc,dddd, ,bbbb,cccc,dddd, aaaa,,cccc,dddd, aaaa,,,dddd, ,,,dddd,
example aaaa,bbbb,cccc,dddd,
example aaaa,bbbb,cccc,dddd, ,bbbb,cccc,dddd
aaaa,,,dddd,

 $ egrep -v ',[ ^I]*,' data2
example aaaa,bbbb,cccc,dddd,

Can you just drop any line with two commas that are adjacent or separated only by whitespace, or that are first on the line? Something like:

 [dynamic<1>butlet]tmp $ cat data2
aaaa,bbbb,cccc,dddd, 
,bbbb,cccc,dddd,
aaaa,,cccc,dddd,
aaaa,,,dddd,
,,,dddd,

 $ egrep -v ',[ ^I]*,|^[ ^I]*,' data2
aaaa,bbbb,cccc,dddd,