I am thinking about getting my dog assessed as a therapet and the only flaw she has is that she often takes biscuits a little bit to eagerly ;)   I'm looking for tips to stop this. 

I have got into the habit of throwing them for her and she jumps up for them or she takes them from my closes hand where she has to snuffle for them which means she never gets a nibble at me.  The problem is going to be that the assessor from the therapets service will probably offer her a biscuit held in her fingers and greedy-guts might snatch it which would mean she might fail the assessment.

I don't use clicker training and don't want to start using it to stop this behaviour so what else could I use?

As you offer it if she goes to snatch withdraw your hand and keep doing this until she gets the message that she doesn't get the treat unless she takes it more calmly.

I do similar and say 'gently'.  If really over eager I close my hand over the treat so they soon learn that lunging equals treat disappears in my fist.  this is good for a dog that might lunge after the withdrawn hand.

I will try that but she is generally fine when I do it but I suppose it is like all behaviours, it is trying to ensure the positive behaviour is also demonstrated for others.  Cue one fat but happy dog as she 'practices' taking nicely - she is not as thick as she makes out lol

My dog is a git for this ! even though he is 9 he still snatches it . He will take it gently if I remind him first. Also putting the biscuit in my mouth then he's as gentle as a lamb :) I sometimes get him to lie down and I put it between his paws in front of him and make him wait til I've said take it too . He is much worse around other dogs plus his eye sight is going !!

We have two dogs the Border Collie is so gentle when he takes from the hand. My Cocker if not reminded to be gentle nearly swallows my fingers. I agree with correspodence above, I say gently and take my fingers away until he sits still, calms down and nibbles it off me.
However with my great niece ( she is nearly 20 months) he steals her biscuits from her sooo gently already. I think he knows its a young child and mugging her should be done gently.
I also tend to get them both to catch food, and put in on their noses to flick it up and catch.
Just teach them to sit still and not be in a rush.

> We have two dogs the Border Collie is so gentle when he takes from the hand.

That's a coincidence!  My Border Collie is soooo gentle, I can hardly feel him, even if he is last in line to be offered a dog biscuit.  My youngest Beardie girl swallows my arm up to the elbow!  Well, it seems like it!  My BC boy has never snatched right from a pup.

I think borders are born gentleman. Our Border Jake is my husbands dog i was determined to let him be HIS dog, I have my cocker but he is so lovely and so gentle, I love him to bits. Jake is only 1 now and already has had OCD in his shoulder and a lot of pain and he has never, ever snapped ot ever tried to wiggle off he is adorable.

My dog is so good when giving treats he sits n stays until I tell him to get it but when he is in company with other dogs he is so greedy I feel embarrast I tell them he is not like this on his own, any tips on trying to stop him being like this.