When looking at the facts and figures, this is not really supported.
http://www.healthaliciousness.com/n...php?o=16109&t=11452&h=16160&s=100&e=100&r=100
And a list of various different beans with their protein figures (all per 100g which is roughly 1/4 of a can of beans (in the UK at least)).
http://www.healthaliciousness.com/articles/beans-legumes-highest-protein.php
Now if my daily requirement of protein is 45g (I'm female and that is the UK recommended minimum) and I have even only have a can of chickpeas (and trust me I can easily eat a can in a single sitting) 100g gives me 8.9g, so half a 440g can will presumably give me roughly 20g of protein, that is almost half my daily amount from half a can of chickpeas. That seems to be a reasonable amount tbh.
Fruit on the other hand will give me what?
Mango (100g) 0.9g of protein
Banana (100g) 1.1g protein
Avocado (100g) 2.0f protein.
And protein deficiency is an issue for any active vegan. A deficiency can lead to muscle wastage, not to mention organ failure as a severe consequence. Other symptoms include fatigue, headaches, oedema, difficulty sleeping, slow healing, thin or brittle hair. I could list a few more, knowing them all too well.
This is an interesting article for anyone wanting to know more about protein deficiency.
http://vegetarian.lovetoknow.com/Protein_Deficiency_Symptoms