Sierra Nevada Pale Ale Clone Advice

I'm brewing this clone kit from Austin Homebrew today and was hoping I could get some advice for the best results. The recipe is as follows:

10.25 lbs 2-row
.75 lbs Crystal 60L

.25 lb Malto Dextrin addition at boil
1 oz Nugget at 60 mins.
.5 oz Perle at 15 mins.
1 oz Cascade at 5 mins
*.5 oz Cascade dry hop in secondary

Pitching Wyeast 1056 American Ale yeast....made a starter with Light DME.

Desired Mash is at 150*F for 60 minutes with 1.25 qt/lb. It says to not run off more than 6.25 gallons in the sparge with exclamation points...however, it says later to add water to make it 5.25 gallons in the fermenter. This is just what the recipe says from AHS. I don't like to add water with an AG brew and don't think I should have to. I want this to taste and look as close to Sierra Nevada as possible. Should I run off as much as I want as long as the gravity is ok? It says here that the O.G. should should be 1.050 and that should be reasonable.

Also, I have never added sugar with the exception of honey to any of my brews. What is that for?

Thanks for the help guys!!

If you know your boil off rate then I don't know why the need to add water at the end. Using the grain bill Promash at roughly 70% you should get your OG. The malto dextrin if for added body. It isn't fermentable.

They say add water in case you boil off more than expected. If you end up with less than 5.25 gallons and your O.G. is higher than 1.050 you should be able to add water without a problem.

Thanks for that! I'm not worried about having to add water and I guess they put that in there so people know that they can if they need to. Typically I run off 6.5-7gallons to get down to about 5.5 gallons at the end of the boil.

I hear a lot on here about filtering out the hops so they don't go into the primary fermenter. Why is this so important? I don't have any kind of filtration going from brew kettle to fermenter. If you are going from primary to secondary in a week or so then all of the hops will settle to the bottom and you can leave them in the primary. Will all of your hops going into primary really effect the taste after those hops have been boiled for so long?

I decided not to use my muslin bag for the hops on this Pale Ale because I didn't feel like I was getting all of the flavor out of them. This one had three hop additions as well as a dry hop in secondary. I know I will definitely taste the hops in this one since I can really smell them coming out of the airlock. My yeasties started pretty vigorously after about 4 hours and were still going strong this morning.