Question about my Bros batch we did together....

Me and my Brother 2 days ago.

12 lbs 2Row.
1 lbs of munich
1 caramel

5 gal all grain batch. mashed at 160 for 75 mins for his recipe.

1 packet of US-05

It's a 9oz hop IPA

anyways I was saying to him we should pitch 2 packs of the yeast and not one. What do you guys think?

What's the OG? One pack should be enough for most standard ABV beers. Double check by using mrmalty.com

Did you rehydrate the yeast first or just dump it in dry?

Not related to your question, but was 160F the temperature of your strike water or your mash? It's pretty high for a mash temperature.

Was going to say 160 is about 6 - 10 degrees high for a mash temp. Ususally you want it around 150 - 152. That said, I think that you'll still get conversion, but I think there will still be a lot of unfermentable sugars left in the wort.
As to the yeast question, presuming you pitched 2 days ago when brewed, it makes no difference now as to how much you pitched. The yeast would have already reproduced to the correct amount needed to do what they need to do, and fermentation should be well underway.
I would let it ride at this point, give it another couple weeks and check gravity. Check again 2 or 3 days later and see if its ready for bottling.

I'll assume your OG came in around 1.070 with that grain bill and not knowing your efficiency? If so, a properly rehydrated pack of 05 should have been a good pitch. If you didn't rehydrate then you lost some cells on the pitch, possibly half!

If your concern is proper attenuation and finishing then I too believe if you actually mashed at 160 then you mashed too high and your FG will finish a lot higher than desired for an IPA