cakegirl i couldnt agree with you more! trust me you are not alone. i have several friends that are also phd students, and we all feel the same way, because we're such good friends, we're completely honest. and i know phd students from different groups and uni's and the consensus is that
1. we all feel that we're fake and frauds and someone will find out that we don't know anything and be chucked out and fail our phds.
2. that we procrastinate far too much that we would like to admit to even ourselves!
3. that we dont really understand what we're doing, but pretend we do!
4. that we have wasted alot of time, on things that did not turn out to be fruitful at all.
5. that we ask ourselves over and over again, why am i doing a phd??? i wish i could go back in time and tell my self don't do it!!