When calculating sugars used in the
wort, how much sugar does honey
contain? Is it closer to dry malt
extracts, raw cane sugar, dextrose?
Honey is loaded with fermentable sugar (think mead...), though not as much as malt extracts. There are "adjuncts" within the honey as well. But you can yet a near-even yield from honey as you could from dry malt/syrup, at least from my limited experience.
When is it better to use it? Boiling
time? Second fermentation?
I've used it in the boil and I've used it (boiled) instead of corn sugar when bottling. But I've always boiled it first to sterilize. Honey--while it won't spoil--can contain pollen, yeast, and other elements that could potentially harbor the growth of nasties in an otherwise sanitary solution. Remember, honey is also an antitoxin, so on its own it won't be affected by anything potentially residing within it.
How intense is the flavor it leaves in
the beer? What if you use honey with
herb aroma? Is there a maximum
quantity of honey you should use so
that it does not cover the primary
flavors of your beer?
It depends on the type on honey, the type of beer, and the amount of honey in the batch. I have used just a bit during bottling to give the beer a nice tacky sweetness, and have used a hefty dose (5 lbs honey and 6.5 lbs fermentable malt sugars) to be a main ingredient. Honey will lend any florals it contains to the flavor of your beer. Of course, if you're using supermarket honey you'll only be getting a mellow sweetness with some very faint florals. Personally, I try to find local wildflower honey from local keepers that hasn't been pasteurized. It lends an amazing bouquet along with the sweetness and spike to the ABV.
Do honey sugars create "sharp notes"
in your beer, and thus "bad" alcohol?
Bad alcohol? No. Sharp notes? It could. It really depends on what you're making.
Is it worth using it prior to bottling
I've used it, as I mentioned above. I've used 1/2 cup honey boiled in a cup or so of water.