dont know what all the fuss is about. i have drilled in the middle of
tiles, between tiles and also at a meeting place of 4 tiles with the
same procedure. I use a hammer drill but without hammer action until i
get through the tile. The only non-slip thing i use is masking tape
but go slow at first. When i am through the tile (the hardest part)
then on to hammer action and no problems.

One thing to bear in mind is that on 1 occasion when i was using a
plug, make sure it goes right through to the wall. i left the plug
flush with the tile once and when putting in the screw, the arrow like
grip things got caught in the tile and whilst tightening the screw, i
was actually pulling the tile closer. Ended up with a cracked tile.
you live and learn.