Do Experts not Imbibe?

Is it true that experts don't imbibe?
That they sniff and sip and spit?
Well, tell me what's the good of it?

I'll tell you now what I have found -
And I've been many years around -
You never really know a wine
Till glasses you've had eight or nine.

The first is rather interesting.
The second is where begins the testing.
The third one I would call "explore"
And the fourth, "Yes, yes; I will have more."

When I come over to your house,
Yes, yes, get the glasses out;
But do not  count it by the glass:
A bottle each, or it's alas!

A so-called expert would have a sip,
But I will have the whole of it.
And if the choice is size or quality,
Then plonk wins every time for quantity.

Three glasses, and I'll say a poem,
And twenty more before I go home.
I'll even do many lines by Heaney,
Corrupted with lascivious meaning.

Here is how a wine is judged:
Does it the joyful spirit move?
Does it the company ignite
To laugh and sing all through the night?

If you wonder, "Is this good for me?"
Don't ask a qualified MD.
Ask a jovial gentleman
Who's been and done and still goes on.