Says who? A random IM company? They tested this on how many domains? I love when people come to conclusions without extensive testing, its just fantastic. Sounds to me like "On February 10th a client of ours recently saw a complete loss in rankings. Needless to say we completely freaked out and began our recovery process however this particular client had previously lost rankings over a year before" really means "this is an article to cover our ass so our client can remain calmed.
Obviously they tell you nothing about their "healthy techniques", so what, are you going to swallow the propaganda and say no to that domain coz they had this issue?
