I wish I had read this page before I first went there in April. Not knowing which route to take, my girlfriend and I turned left where OP says you have to go right. This resulted in us diverting into successively smaller and wilder paths. We had to do a somewhat extreme bushwhacking to reach the eastern summit, where apparently nobody had been in years. We then took the southern, veeeeryyyy sunny route in search of a passable trail. We ran out of water and had to help my dog on the steeper parts. Pretty adventurous, but also kinda reckless.
I went there again in July, took the right trail and reached the summit in c. 50 minutes. What a difference!
The hill has recovered well from the fire it suffered years ago. What I like particularly about the Cuatlapanga is that it is full of pineapple sage (Salvia elegans), so the whole trail smells very good. The views of the surrounding mountains are also something else.
I went up on a sunny day early December. Had great views of La Malinche. Nice short hike, very enjoyable.