no, actually it does matter. Browser caching is not reliable and only covers around 20% to 25% of requests (according to GoogleMaps JS caching behavior stats). So it matters quite a bit.
Towards the end of the article
>> Suprising Results
40-60% of Yahoo!’s users have an empty cache experience and ~20% of all page views are done with an empty cache. To my knowledge, there’s no other research that shows this kind of information...
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