I think that comment referred to touch-gestures, i.e. pinch zooms. In those, tile loads cause the touch gestures to stutter. 

On Aug 5, 2013, at 7:12 PM, grondak <notifications@github.com> wrote:

> In map.js:
> 
> > @@ -911,20 +908,48 @@ var Map;
> >        this._rd_cb = function() { self.invalidate(100); };
> >      }
> >  
> > -    // TODO: Defer loading of new tiles while in the middle of a zoom gesture
> I think it is valid. I zoomed my wheel very quickly and wound up waiting for a while as the successively-higher rez tiles were retrieved. However, that is a useful situation for zooming out, because the lower-rez tiles will be at the browser. Your call on this one. I kinda like the way the site works currently.
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