Is it normal?

On the odd occasion Roman, my seventeen week old, will blatantly ignore my 'sit' command....is this normal?

Yes, Roman is just a puppy and learning

Yes it's normal 17 weeks is still very young and they are really still just a baby at that age.

I'd think so. Infact at any age I think they may have their temperamental moments

yes its normal, they have slective hearing

i think every dog regardless of age will develop selective hearing and push the boundaries soemtimes. its all part of growing up and developing their own personality