Font Combiner – improvements to free web fonts

I see clear difference on both Windows and Linux, your product makes the fonts more clear and sharp thus making it more readable and less fuzzy than taking fonts straight out of Google Fonts. Looks to me like a solid thing, definitely bookmarked.

On my Mac+Google Chrome the difference is barely noticeable.

Same here (OS X, Safari). It doesn't look much better in the demos either. Their demos include some truly horrific examples, like Linux, Firefox 24, Ubuntu: http://fontcombiner.com/docs/media/demo/linux_firefox_ubuntu...

From the explanation beneath "How is this possible":

> The Font Combiner application uses a couple of different techniques to overhaul fonts. All glyph forms are extracted from vectors present in the original fonts and scaled to size where appropriate, the vertical metrics are recalculated from scratch, and spacing and fresh automated hinting are applied to the result.

Now, I don't know a lot about the gory details of typography, but I do know that type designers spend a lot of time thinking about things like "appropriate size and scale" and other metrics. Can these really be automatically recalculated from scratch and how can this possibly lead to a better result?