Date Performance

i pubblished on my blog some test about Date, DateTime and Time
formatting performance, it's in italian but the data it's in english,
i think it's quite stranghe since it show how base ruby can't manage
Date and DateTime formatting using strftime while Time it's fast.
I've tried a library that incredibly decrese the time required by
strftime (something like 14 sec for 50000 cicles vs 0.30 sec for same
number of cicles)

You can see test result at