Flooring Tile - Silicone on grout in Shower?

I have 12x12 porcelain tile on my shower walls and my builder put clear silicone on the grout where the tile meets the shower pan at the bottom and along the wall edge where the glass meets the tile, in addition to the wall edge where the tile meets the tile.............going upwards.
He said he likes putting the silicone around these edges so water doesn't seep.

Is that necessary? Or does it not matter?
Is he being overly cautious or trying to prevent something?

Grout and tile are not water proof to begin with, but silocone is used at change of planes.

If he built the shower pan correctly, any water would not get past the pan liner anyways. The pan liner should have been installed on a presloped mud bed so any water that does get below the tile and final mud bed can go down the drain weep holes.

Smart people would use Ditra and Kerdi


Schluter-DITRA - Schluter-Systems (http://www.schluter.com/6_1_ditra.aspx)

If "SMART" people use Ditra & Kerdi......then I'm a genius! :D

Jaz