Just as a point of reference I ran this 30k [1] (18.6 miles) at 8:38 pace vs. a flat road half marathon (13.1 miles) at 6:41 pace about 5 months later.
As you can see in this [2] it climbs from a low of 2500 feet to 3700 feet. I'd estimate 1500 feet total so much less than in the article.
I usually place in the top 5% of men in most races.
