Thanks for the explanation. Not sure I really care for the 4e Healing Surges. :-\
So as you go up in level, it takes more to wear you down (more hits, bigger/tougher/more dangerous hits, higher level spells, etc.). But it always takes about the same number of Healing Surges to get you back up to max? That seems off balance...
That's because your healing surges scale with you. Depending on your class and Constitution, your healing surges serve as a "reserve" pool of 150 to 300% of your hit points (theoretically possible to have more, but that would require an actually high Constitution, and IME most people settle for "OK" in favor of having better active stats).
Interestingly, Constitution affects this reserve pool much more than your actual hit points. 1st level hp go from 10+Con score (wizards) to 15+Con score (fighters, paladins), and Con does not affect later-level hit points. So for a 10th level fighter, the difference between Con 10 and Con 16 is going from 79 to 85 hp, which is not a big deal in the grand scheme of things. But they also go from 9 (225%) to 12 (300%) healing surges, increasing their total hp per day from 256 to 340, an increase of almost a third.
Also, if I am out of Healing Surges and the Cleric casts a healing spell on me, I get just a small benefit from it? Why have a Cleric? Let's just grab healing potions and be done.
If you're out of healing surges and the cleric casts
healing word, nothing happens. Same if you drink a healing potion while out of surges. You're just too wiped out. If you need more healing, clerics
can have
cure light wounds (2nd level utility prayer, heals as if you spent a surge),
cure serious wounds (6th level utility prayer, heals as if you spent two surges), or
mass cure light wounds (10th level utility prayer, heals all allies within 25 ft as if they spent a healing surge and adds your Cha bonus to the healing done) – but that's a cleric that's extra-focused on healing at the expense of prayers like
bless (2nd),
divine vigor (6th), or
shielding word (10th).
And why have a cleric, indeed? One of the goals of 4e was to make party setup more flexible. In most editions, you pretty much
need a cleric, because you need that sweet healing. In 4e, healing is part of the Leader role, so a Warlord has the same baseline healing as a cleric, and so does (more or less) the later classes of bard, artificer, shaman, and probably ardent. A leader generally also deals some damage and hands out buffs.
Also, the job of a Leader is to heal you
in battle. Between fights, you don't need an external source to trigger your healing surges (though you do get some extra mileage out of them if you have a leader using their
healing word or equivalent).
Maybe I have been conditioned from all the other D&D editions I have played, but I like the traditional trope of higher level heroes needing more healing to get back up to top form. And I also like the 5e view of having separate internal (Hit Dice) and external (Clerics, Paladins, cure wounds scrolls., potions of healing, etc.) healing as resource pools.
And that's a matter of taste. I believe this is one point where 4e has a better structure than 5e, but it's not like I'm arguing that this is objectively true. What
is objectively true is that hit dice do not serve the same role in the game as healing surges do, except on a very superficial level.
From a historical point of view, I'm pretty sure that the reason for healing surges can be spelled "
wand of cure light wounds". The 3e DMG has a whole bit about adventure/dungeon/encounter design that boils down to "a 'normal' adventuring day should have four encounters, none of which is particularly dangerous on its own but soak up resources like spells or hit points, which means the fourth and final encounter actually poses some challenge." But CLW wands meant that you could easily heal up to full out of combat, so hp was no longer a meaningful daily attrition resource. To compensate, many DMs increased the challenge, which in turn meant that casters would use more spells on offense, which meant that the casters needed to rest sooner. And thus was born the 15-minute adventuring day. Healing surges were part of a greater focus on the encounter as the adventuring unit, while at the same time providing a daily attrition resource.