A somewhat more informative answer:
Weapon condition is a multiplier to damage output. So 99% con does 99% damage of 100% con. Note that this is truncated, so if your proper damage at 100% is 69.3 (speed 4.2 weapon, 16.5 dps), then you'll actually do 69 (losing the 0.3). The same weapon at 99% con will do 68.607, truncated to 68.
Likewise, armour condition is a multiplier to AF. So 99% condition on all your armour pieces means an effective loss of 1% of AF. Note, in case of AF, that your bot's AF buff is more than large enough to cap your AF as long as your con is somewhere above 90-low percent.
In other words, repair your armour when con gets down below 95% or so, repair your weapon when con gets below 100% (or some lower value that makes you happy, remembering you're losing 1% damage for every point you let it drop).
Note, by the way, that quality works the same way as con does, but it's constant for the weapon/armour piece. This means that while you want 100% qual for a weapon, it's not nearly so important for armour as long as you have a buffbot's AF buff.
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Angharad Macsen, Legendary Smith
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