I am a Sicilian player.so many time I have to face alapin variation.in opening books (like expert on anti Sicilian and starting out : Sicilian defense) it is mentioned 1.e4 c5 2.c3 Nf6 3.d3 is dubious.why is it so? I didn't found any explanation in books of it.although I know.white has compromised space but still what I am missing about it? many player has played it against me.i didn't found any huge advantage from that position.please anyone can explain??