Maybe its just my experience, but Id disagree. Had a Felt Q720, with a Rock Shox Revelation fork and lockout I added, and climbing was great until you hit anything. The rear tire, because it has no play, tends to jump up for a split second as it goes over roots, rocks, etc. My old Giant Trance , because the rear suspension has a rebound pushing back into the ground, hugs the ground a whole lot more when Im climbing. My Strava times are proof of it. Way, way faster on the Trance. From day one even, and I was very schooled on the hardtail. That split second where you are really cranking and it seems like a gear slips or something, when your rear tire hops over something before it comes back to the ground is what Im talking about. I can just straight up crank on the Trance and it always has traction. Its older also. Also, not sure, but I think my Trance is much lighter than the Felt I had. So that rule would only apply sometimes. I certainly woudnt get rid of the Trek if it were me. Just smoke em on the dowhill sections.