I delete emails and sms messages all the time. It's not necessarily evidence of any wrong doing.
There was an independent investigation that made a recommended to GWS that there was nothing to be concerned about.
As 'dodgy' as the story about Whitfield trying to avoid an obsessive girlfriend sounds, it's still a plausible explanation.
Carn. It's not as if it was junk mail being deleted. It was specific and it's damning that it was deleted.