The rule still applies.....The further you move from the correct diet the more problems you are likely to see.
Do'nt get me wrong rabbits love the occaisional treat but consider this..... the average medium rabbit is about 2kg and the average human is 75kg.
If you feed a rabbit one grape you are in effect size for size feeding 35 grapes to it. If you cut a medium banana into 7 peices you are in effect feeding 5 bananas. If you give your rabbit the knob off the cucumber you are in effect probably giving it size for size the equivalent of the whole cucumber.
Our advice is avoid "man made" and grown veg and always offer handfuls of grass small amounts of natural veg i.e dandilion or things like parsley or parcel or other herbs that have large amounts of fibre in them and never fruit.
I see there is yet another thread starting up on feeding veggies to rabbits and yet the message of what rabbits are , where they have come from and what they would eat in the wild in their natural environment seems to be ignored by the majority.
We have been re-homing and specialising in rabbits for the rspca local branch for 10years In that time we have seen 100's of rabbits and whats more we have had the rear teeth inspected both visually and whilst anesthetised at neutering of all of them. I can tell you from our own observations that between 25-30 % of all rabbits that come to us have rear dental problems in the form of spikes ,spurs and rear dental absesses. These in the vast majority of cases are aquired dental problems as a result of the wrong diet.
If you took out of the figures those bunnies born with us or under 4months of age then that % would be higher.
Sorry to rant ....but this is serious and every caring owner should be aware of the serious consequences if you ignore it on teeth alone and thats before you take into account all the other gut problems this can cause together with sticky bottoms, flystrike and whatever.