My thought would be that since both a small amount of glucose and of salt mixed in water constitutes a rehydration solution, it would likely satisfy thirst (though it isn't something I would give a pigeon as a matter of course). JMO.
I agree, the key word is well balanced. You may not agree with ACV, Garlic, or even a little honey after a hard day of flying and that is fine. But there is nothing wrong with it either. To much or too little well balanced pigeon feed is also not good for the birds either.I have to reply. If you give a pigeon a well balanced diet, found in all pigeon feed. You have no need to give them supplement's.
Just like a human body, we only need so much. More is not better, in fact it can become detrimental. Ie:I eat two orange's a day. If I ate twenty I would not feel better, or benefit from it.