It could just been a coincidence that you had a below avg WAR for that fight, or he had bad luck on his weaponskills. I think they need to buff PLDs damage to keep up the mindset of all group content which is out there. Atm all you need is an AOE skill and you have a fairly high chance of peaking the damage charts. For a tank this also includes being able to keep hate on everything.

There is two compleatly diffrent discussions about PLD, one about single target content and one multi target. All PLD experiences are from the few chances I've had as PLD myself at times.

General tanking cases
Damage reduction: I havent done any long parses to compare since I never have a PLD tank around, but I'd say PLD and WAR have a tie. Most big mean bosses do few auto-attacks compared with normal trashmobs and thus making a PLDs blocking ability less useful. Say all your blocks are 50% dmg reduction, WAR makes it up with having both featherfoot and foresight which reduces dmg all down to 1 dmg or a miss.

Survivability
Yet again I see a tie here depending on situation.
PLD have support abilities that enhance the whole group. Divine Regen, Rampart, Holy Succor. Where as WAR only have self abilities, but combined with an increased HP pool helps the WARs surivability by alot. If you take in consideration all the healing a WAR gets through second wind and rampage through critical attacks and WS it adds up to quite a bit.
The low HP pool of PLD makes it hard for a PLD to utilize Holy Succor effectivly, the WHM is always on his toes, most cases landing a cure before holy succor goes off which drasticly reduces the amount healed. And even the time required to cast Holy Succor puts PLD at a great risk when he first has to time between attacks and in addition need to dodge skills. A badly timed spell will result in lots of extra dmg taken. No way a WHM will give a PLD buffer to "maybe" manage to cure himself. And lastly, to benefit from cover mp regeneration you gotta time it pretty well or you just lost the game, if the mob decided to do something else then dmg you (like jumping around on field using skills) that cover went to waste and you gotta drag on with almost no MP (which in imo is over half the reason to be PLD) until cover is back up.

Damage:
PLD has as good as no dmg. You got that awsome Spirits Within which deals a consistent 450ish dmg once a min. Even a WHM could toss out some nukes and probably be on par on the total dmg. And a WAR dishes out 4-10 as much damage depending on the situation.

Single Target Enmity:
Keeping highest enmity (which translates to having the mob's attention) is fairly simple for PLD. This is a non-issue compared with WAR, lets face it, we need to compare PLD with WAR on every aspect cause WAR is everyones fav tank-o-damage. A dedicated WAR tank will most likely be on par or in some cases better then a PLD again depending on mob.

Multi Target Enmity
PLD has a big big problem in this area, sure you got AOE flash and war drum, but as soon a DPS or mage mistakely toss out an aoe nuke or mistakely pokes wrong target that mob is gonna turn to them instantly. At the same time you gotta use the remaining enmity abilities you got on the main mob to make up for the low damage dealt enmity. A WAR can just toss out a steel cyclone and we pretty much got everything and still have it after an AOE nuke/ws or two from other people.

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And with all the content released which gives reward for speed run this and that, PLD dosent quite make a good position. I want a tweak that makes PLD viable for all excisting and new content, speed runs included without giving rest of the group a harder time due to my lower DMG output or whatever the catch might be.