Designing Kitchens and Bathrooms - grout and caulk: he said, she said

Hi,
We are having a bathroom remodeled. In the bathtub area, the walls have ceramic tiles. One of the contractors saw that there was no caulking where the wall meets the bathtub, so he added a line of clear silicone caulk around the top of the tub and up the walls in the two corners. It looks good. Well, a few weeks later (project is still going on, we have never even used the tub) we noticed a crack in the grout where the two corners of the wall meet. We want the tile guy to fix the grout. He said you should never add silicone caulk over grout and that it will be a huge pain to clean out the line. The grout in the bathtub is sufficient and it shouldn't need caulk. Here are my questions:

1) Is the tile guy correct? Why would he say you shouldn't caulk around the bathtub (and up the wall corners)

2) Are we being unreasonable saying he should clean out the caulk and redo the grout. We have never even used the tub and there is a crack.

Also, around the toilet there was no caulk so the first contractor added some. The tile guy now says we should have grouted around the toilet and not used silicone caulk.

This has been a fiasco. I think the tile guy is just complaining because we want him to redo some of his work. What do you guys think?

Thanks

Caulk where two walls meet. No grout in this joint.
Caulk where the tile meets the tub. No grout in this joint either.
Around the toilet, some say caulk, some say don't (optional).