What do you mean by brush it in? Do they have loops like a layout blind blind to stuff grass and stuff in it? What if I want to hunt in a hardwood forest but don't have the money to buy several tree stands? There's no real way to brush it in when it's just tall hardwoods but will it really spook them that bad?

Hunting from a blind has its downfalls, but I like doing both. From a treestand, you can see them coming from much farther away. Often times with a blind in the woods, you wont see them untill they are right up on you.
When setting up a blind, I think of these; SHAPE, SILHOUETTE, SHADOW. Just make sure nothing looks weird from the deer's perspective, and you are good. I have also made the mistake of keeping my pop-up blind in the closet in my house[:@]. Talk about ****ty scent control, I saw nothing that day.

Brushing in means set your blind between 2 trees, bushes or whatever. Then find some downed tree limbs and lay them in front, beside, and maybe have 1 leaning across the top. Find some grass and throw that in there also. Mainly just break up the outline of your blind. Make sure you check your shooting lanes.

I cant hunt from a ground blind without alling asleep