The visit, dismissed as a mere social visit by both sides, fuelled the speculation about a possible switch to Red Bull for the 2008 world champion.
"It was a misjudgement by Lewis because it gave ammunition," Whitmarsh told the Daily Mail. "I feel sorry for Lewis because I know he is a little bit more sensitive than me on these subjects.
"I went to see Christian (Horner too) and I don't think I am going to join Red Bull next year!"
26-year-old Hamilton's sensitivity was evident this week when he reacted to Niki Lauda's latest criticism, and to the advice of former champions Nigel Mansell and Jacques Villeneuve about the wisdom of staying at McLaren.
"What Niki Lauda thinks about me, I really couldn't give a toss about it," said the Briton.
And as for Mansell and Villeneuve, Hamilton added: "I find it kind of funny and am not sure anyone really cares what some people think. If you have an opinion, just keep it to yourself."