In article wd9yg.13519$S_1.13140@trndny05, says...
All,

snip

The tile is designed to slope to the drain and it does, but the tile guy
didn't set it quite the way I wanted, and it as such the first tile
around the edge is steeper thant the 6 or 9 in the middle. This causes a
little water to remain in the grout lines till it evaporates. Hasn't
been a problem, but I have noticed that in these areas [and not
elsewhere] there are some 1/8-3/16 inch diameter voids in the grout.

That sounds pretty bad. Those aren't voids, he cheated you out of
grout! ;-)

the
grout also has an overall spally feel, like a little bit or sand comes
up when you rub it with your finger, where it doesn't elsewhere. I have
some of the grout in the garage[packrat] and can effect somekind of
repair, but am wondering if there is a more permanent solution.

How old is the grout? If it's been opened, I wouldn't use it if
it's over six months old. I don't think a piecework fix is going
to work anyway. You might have to cut out the grout and start
over.

The tile guy said the grout 'didn't need' to be sealed. The grout bag
said you could so I did. Is it possible I didn't seal this area well?

....and cause huge holes like this? Is the subfloor under the
shower stable? It sounds like you're getting flex in there that's
causing the grout to fail. I doubt it's the sealer (how can you do
that wrong , but I'm just a DIYer too.

My plan is to dig out the small holes and fill with new grout. I jsut
would like to do this once.

I'd cut out all the grout and replace it.

--
Keith