You surely must be kidding here... the power is called "Life Transference". That alone should make the intent clear.
Transfering your life force from one part of your body to another? C'mon...
Bye
Thanee
You'd think. But the developers are very keen on the differences between ally-affecting and creature-affecting. Given that the default for leader tends to be 'ally-only' then one cannot rationally presume that they'd overlook that tendancy for a utility power.
Now, I know this may come as a shock, but D&D fourth edition IS the most playtested roleplaying game ever made.
I know. It doesn't seem it, but it is true.
This stuff gets playtested and developed for many many months.
The original design of the power might have been 'Use on ally' but the possibility exists that over the course of development, someone said 'Is it bad to use on yourself?' and after a bit of time playing it they said 'Actually, that's a pretty cool interraction.'
And thusly, the power stands as it is now.
I've also heard some people -still- claim that encounter powers used during short rests to heal isn't intended design despite the existance of feats that explicitly bolster powers used to heal during rests.
In the end, it is not safe to assume designer intent regarding this. It isn't RAI that it only affects allies, because the rules technology exists to make that happen, and has been used to that affect for every leader class in the game for powers at every level, in every source book. Seriously.
The case is that it isn't 'Rules As You'd Like It', or RAYLI, which I can certainly understand. Personally, I'd not mind if it said 'allys only' either. But the power IS cooler this way, so I can understand why they decided to go with this version.
The real question is if the power is a broken effect during combat: It's a standard action, costs you your attack, so it extends the length of the fight against the monster, so it'd had better be good healing for who receives it. So from that yard stick, it's doing what it should. It's a good power. Is it a -great- power? I dunno.
Does it prevent more damage than Sanctuary? Is it more helpful in a fight than Knight's Move or Moment of Escape? Swift Mender/Aid Other/Saving Throw Power of Choice here? Bonds of the Clan?
Hard to say, to be honest. The power does swing the battle a bit more to your favor... but if a power doesn't, then it's a wasted slot. But is that swing too great? Or does your now weakened condition make your more vulnerable?
And is having a free healing surge for yourself available in every combat worth that utility slot?
And lastly, is free healing outside combat, to bring you to full, really so broken it requires errata? Does it make the game unfun, and unplayable? Does it make encounters trivial?
I don't think it makes Cleric absolutely necessary by having this ability exist. If all my leader can bring to the table is 'I bring Moar Healing' then he's not as useful to the party as a leader who can heal us enough to win the encounter, but also can help us win that encounter faster, while keeping our more vulnerable members out of harms way.
A leader can heal away the injuries... a great leader can swing the battle so he doesn't have to as much.
Moar Healing doesn't do the latter aspect.