It is, indeed, a trial to maintain the virtue of humility when one can't help being right.

DEAR MISS MANNERS:
Should you tell your mother something if it is important when she is talking to company? I am six.

GENTLE READER:
Yes, you should (after saying "Excuse me"). Here are some of the things that are important to tell your mother, even though she is talking to company:
"Mommy, the kitchen is full of smoke."
"Daddy's calling from Tokyo."
"Kristen fell out of her crib and I can't put her back."
"There's a policeman at the door and he says he wants to talk to you."
"I was just reaching for my ball, and the goldfish bowl fell over."
Now, here are some things that are not important, so they can wait until your mother's company has gone home:
"Mommy, I'm tired of playing blocks. What do I do now?"
"The ice-cream truck is coming down the street."
"Can I give Kristen the rest of my applesauce?"
"I can't find my crayons."
"When are we going to have lunch? I'm hungry.

Eating grapes with a knife and fork is not what one would call refined. It is what one would call ludicrous.

GENTLE READER:
You, sir, are an anarchist, and Miss Manners is frightened to have anything to do with you. It is true that questioning the table manners of others is rude. But to overthrow the accepted conventions of society, on the flimsy grounds that you have found them silly, inefficient and discomforting, is a dangerous step toward destroying civilization.

DEAR MISS MANNERS:
When does a gentleman offer his arm to a lady as they are walking down the street together?

GENTLE READER:
Strictly speaking, only when he can be practical assisstance to her. That is, when the way is steep, dark, crowded, or puddle-y. However, it is rather a cozy juxtapostion, less comprising than walking hand in hand, and rather enjoyable for people who are fond of each other, so Miss Manners allows some leeway in interpreting what is of practical assisstance. One wouldn't want a lady to feel unloved walking down the street, any more than one would want her to fall of the curb.

Nowadays, we never allow ourselves the convenience of being temporarily unavailable, even to strangers. With telephone and beeper, people subject themselves to being instantly accessible to everyone at all times, and it is the person who refuses to be on call, rather than the importunate caller, who is considered rude.