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Yes. Also, shorter chain flexes less, as do shorter chainstays - in theory.
I would have thought Mr Marginal Gains over there would have grasped this, but I'm dying to hear the explanation as to why it isn't the case.

Let me count the ways.

Shorter chainstays = worse chain line (i.e. it has to bend sideways more to reach the sprockets). That's a loss of efficiency.

Shorter chainstays only flex less if you don't make them stiffer to compensate, it doesn't take much material to win back the stiffness lost through a small (~5%) change in length between too short and just right.

Excessively short chainstays make climbing steep hills problematic, as the front wheel lifts off the ground. You have to change to a non-optimal position on the bike to prevent this.

Longer wheelbase means more bump attenuation for the rider even with a perfectly stiff frame. More comfort can mean more speed over long stages.

Of course, shorter stays and a shorter chain will be lighter, but in the balancing of desirable characteristics which will yield the fastest bike over a given course, 100g or so of weight difference is rarely worth bothering about, much less placing near the top of your priority list.