Realistically, this is probably a rare, but it does have pretty distinct limitations as far as damage prevention is concerned.

Can an Enchantment have lifelink and have that ability do anything?

Trying to figure out if I can ditch the last clause.

You can indeed. It raises eyebrows, but it works fine. I did it in Sienira's Facets, the first set on Multiverse, with Seal of Chastisement :)

Awesome!

Just because you can, doesn't mean you should. This strikes me as being strange for strange's sake. If it said ", Tap an untapped creature you control: Pact of the Dawnblade deals 1 damage to target player and you gain 1 life," it would do the exact same thing.

I just don't want a player to gain life if damage is prevented, which I believe your wording would do. But I could be wrong.

I think your interpretation of the rules is correct, but does it really matter if they gain the life, or are we just too much in love with the lifelink concept?

I agree the lifelink concept is very cool, but I'd suggest alternatives, for instance, an enchantment that grants lifelink to all your enchantments, or a lifelink+ping creature.

OTOH, wizards have been willing to "use a keyword just because it's cool" on Puncture Blast, so there is precedent.

I hate to say it, but I think dude might be right. I do like to see lifelink (and deathtouch, wither and infect for that matter) end up on cards that aren't creatures, but, if I was working for Wizards at least, I would insist that whenever we broke new ground for a mechanic there was a solid reason for doing it... I'd want the card that broke the rule, and could therefore usher in cards that feel natural, and not rule breaking, to be unarguable in of the fact that what the card was doing could not be done unless the keyword 'lifelink' was involved.

At first I was going to suggest that 'damage done was equal to that creature's power' would make lifelink matter, but I guess you could just gain that much life there too. Also, the fact that the damage, and thus the lifelink, can be prevented is more a technicality than a reason. And, anyhow, if you really wanted that, you could add ",if you do," and get the same result. Lifelink is tricky like that... you can spell it out pretty easy, so there are few cases where using the word lifelink adds anything to a card, unless it is used in a common fashion across many cards.

Maybe that't the real trick? If you had a block with a pile of artifacts and enchantments that had lifelink as a theme, then the barrier could be broke all at once. On the other hand, one card with an arguable use of lifelink doesn't feel like a precedent so much as a mistake. Building on it, would feel like building on a mistake.

Blah, blah, blah... semantics. I may think too hard about these things some times.

I didn't really think this would be such a thought-provoking thing, as all I really wanted to do was cut down on the number of words and this seems to be the most efficient means to do so.

­:/