I think Dirrell exploited gaps in Froch's defense better than Haye did Valuev, while Haye kept better composure and avoided being hit cleanly the whole night without excessive spoiling.
Froch and Valuev are two different boxers though; Valuev is rangy and awkward but offensively impotent - Froch is incredibly strong but crude and indisciplined.
Froch is better than Valuev...I believe that Dirrell displayed better offence than Haye did and had to be quicker movement wise to get away from Froch than Haye did with Valuev.
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