corn sugar....added at boil..

In my quest to find my "death by malt" brew, I've recently discovered that some of ya'll are adding corn sugar at the beginning of the boil. Does that add to the maltiness? I've plugged this into a brew calculator:
6.6 LBS plain amber LME
10 ounces corn sugar
1/2 LBS of crystal 80L, carapals and munich grains for steeping
.5 ounce of Williamette for bittering and finishing
and got a nice 15 IBU's and 5.7ABV.
But, will all that corn sugar cause the primary to go ape $hit? Was thinking about going with Windsor dry yeast, not doing liquid yeast as of yet.
I going for more fruity, malty, ester-ry type of brew as opposed to high hoppy style. How you IPA lovers with 60 to 100 or so IBU's like that is beyond me. It just leaves a bitter after taste in my mouth and I have to have some water with it.

As far as I'm aware corn sugar is just a cheap abv booster and will add no maltiness, not much flavour or body, just ABV.

No. What sugar adds to a beer is fermentability. While the sugars from malts are about 75% fermentable, corn sugar is nearly 100% fermentable.

So the more of it you put in your beer, the lower the FG will be compared to an all-malt wort of the same gravity.

If you want super-malty beers, consider steeping grains like munich, vienna, aromatic, biscuit, melanoidin. (I'm not certain if all of those can actually convert in a steep.) I know you can get Munich LME as well.

Then choose yeast strains which are described as creating a malty profile. And, of course, keep the hopping low.

Hmmm, not too worried about ABV at this point, want more malt taste. I did do some research and had thought that the grains I mentioned above would do exactly that.

They will. Good choises, just forget the sugar.
Add DME if you want to boost the ABV and it will give more body and some maltiness.

If you want more body add some maltodextrin.

Since there is no calculation for maltiness, if I increase the grains to say 1 lbs each, you think that would kick it up a notch? I know it will raise the abv some, but I believe I'll only get 75% of those grains in the form of fermentable sugars, now the 25% that's left over, will that be the contributing factor to maltiness??

Yes, but it depends on the grain you are using as to what the flavour from it will be, obviously darker grains will give a more roasty flavour.
I've not checked but the I think the Munich is a base malt so steeping it will not add any large amounts of fermentables because it needs mashing.
It also depends on the attenuation properties of the yeast you use.

Man, so much to learn and understand still. So, if I am limited to steeping at this point, what would be my grains of choice for adding a malty taste? The crystals? Just use more or the carapils? One of the kits I used from Brewers Best was a American Amber and it was pretty good. It used 8 ounces of crushed crystal malt 60L, could I up the amount and say go with 1 pound or more? Maltodextrin you say.....maybe I should try that.

The grains section of morebeer.com has good write-ups on what kinds of flavors each grain adds, and whether it's starches can be converted by steeping. Try doing some research there.

As far as crystal, maltiness and sweetness/body are not the same thing (although they're pretty closely related, IMHO.)

A beer can be very malty without being sweet, and vice versa.

Crystal malts add body/mouthfeel and sweetness. Maltiness comes more from high kilned malts like Vienna, Munich, Biscuit, Aromatic; from mashing techniques, and from yeastb strains that bring out maltiness.

Check out the Wiki link great Malt and Adjuncts section.

Don't take my word on the Vienna, go check it out.