it's not a rule set in stone not to have more than 3 pieces of fruit per day. I have most of the time 5 pieces or more, and on the top of that 3 or 4 portions of vegetables, and I'm at goal, maintaining and often losing a lb or 2, even if I don't need to. And I eat all my dailies. I eat most of my weeklies too - or rather, I go at a Chinese buffet on Sunday night and don't worry about the diet too much, and I calculate my 49 gone because I also have a dessert and a starter... I weight just over 8 stone, I've put 3.5 lbs on during my Christmas break (1 month!) and last week I've lost 1 lb already to get back to pre-xmas weight. When I'm peckish, I eat fruit. Normally just 1 banana per day, but I have grapes, apples, clementines, pinapple, kiwis... everything.
Everyone is different, but I wouldn't stop at 3 pieces of fruit per day, especially in the summer when my fave fruits are out. Well, I also love egremont russet apples during the winter...