I use crafted weapons and boost them with Tenebrium. I don't see why you would make that comparison (stock Tenebrium weapons vs. crafted weapons). I have yet to find any legendary that is better than what I can craft myself and then boost with a whetstone/bowstring, tormented soul/sextant and finally a tenebrium bar.
And I have yet to see a crafted weapon beating a legendary boosted by a whetstone, a tormented soul, a tenebrium bar and finally an elemental essence

.
Only if you regard the additional bonusses of legendaries as completely useless (like the 20% stun PLUS 10% mute PLUS additional strength e.g.) you may come to your conclusion. Even then barely.
Regards,
Thorsten

For comparison, here's what's possible to craft at L20:
2H Axe (265-530 Damage, 2x Crit Damage, +24% Crit Chance):
http://i.imgur.com/Gy6Dubu.png1H Axe (163-327 Damage, 2x Crit Damage, +14% Crit Chance):
http://i.imgur.com/vH9g422.pngSword of Planets (286-328 Damage, 1.5x Crit Damage, +0% Crit Chance):
http://i.imgur.com/ixDUElp.png2H have supreme damage potential but 1H have better defense because of shields. The Sword of Planets is nice as a defensive weapon, but is inferior in terms of damage to a crafted 1H Axe with a crit bonus because the SoP has an lower crit multiplier and
ZERO crit chance bonus. Anyway, I have never seen a Legendary which has better damage potential than this 2H axe or this 1H axe. If you have, then please post it.
The way how these % chances to apply extra effects work, they are not as useful as they seem especially in late game.
Evey point in willpower enemy has, will reduce that chance by 10%. So 2 willpower enemy will completely ignore effects of 20% stun.
Still, those effects are good in early game, especially against basic enemies.
Also, stun itself is really great, since stun change is increased by extra 30% if enemy is wet, so is much more useful then some other effects.
This. The problem is that legendaries don't do nearly as much damage as crafted weapons and the paltry bonuses don't compensate for this (most legendaries don't even have double crit chance bonuses, unlike some crafted variants). Given the choice between having a roughly 1 in 4 chance to deal double damage and having a 1 in 4 chance to have only a *chance* (modified by the target's BB/WP) to inflict some status effects, I'll take double damage.