I'm pretty sure that what Shoultz is trying to say is that while the max damage cap of the Brute was lowered, it hasn't affected the average shot damage that the Brute tends to do, which is around 400 - 500 most of the time.
Yes, that means that there's no more potential for those 800+ hits, but the 400 average damage is still around due to the more forgiving minimum damage that used to be a failsafe that kept the Brute in line (for the most part).
As for the burst damage, it's really reliant on how you perceive it. A Brute can manage to outdamage a Spartan if the Brute hits 400 twice while the Spartan hits 200 or so for all three shots and the other way around if the Brute hits 200 twice and the Spartan hits 400 (pretty unlikely) three times (seriously unlikely).
So, whether the Brute is better than Spartan or not, it could potentially be agreed upon that the Brute is now more likely to deal consistent damage without the low minimum holding it back.