Not to defend the cheese that is the WL class, but you can't myopically look at a single 1v1 instance and base your opinion on that. Many classes can beat a WL 1v1, some conditionally/situationally, others can win in almost any situation.
My RR6 Heretic rarely loses to WLs and has on many occasions beat 2 of them in 2v1...yes they were bad WLs, thankfully bad players flock to cheese classes! ;-)
My Minstrel probably has the best record against WLs of any class I've played. Between the ML10 Cloak Silence, PS, FZ, Mess, insta Stun, it's just way too much CC for the WL to handle, and the pet brings the DPS. Before the recent WL adjustments a RR11 WL hit my R9L5 Minstrel for 1400 damage in a single chamber...and he lost that fight.
No one has even voted Minstrels, but against most Casters they certainly dominate. Valewalkers aren't even listed, yet they give any pet Minstrel a very tough fight that usually can go either way if you play perfectly, but even a well played ~RR5 VW can often dirt nap me so fast it's not even funny. That root style combined with Disease, 2 ranged instas and nasty nasty LTs, almost plate-like armor, and extremely strong melee DPS with an easy to land side stun combo that'll definitely put your lights out if you don't purge it. So are VWs OPd? Depends on what class you ask and in what situation.
Solo 1v1 a Reaver can beat most classes in the game, but in 8v8 they're unwanted and largely unneeded. (too CC prone) I'm certain that a well played Reaver can down your average WL quite easily, but obviously not if he gives into being kited to death. If he can draw the WL in close before getting WTF-mangled, there is a good chance the Reaver can win if all his toys are up.
Other classes that give even a pet Minstrel problems are now of course Assassins with the crazy DD poisons. I think any hybrid and even WLs are having a hard time surviving that kinda DPS output from especially SBs who swing the OH every time. The same can be said for Champs, Valks, Dem Vamps, etc. All of them OPd in some aspects, but in general are fairly balanced. Valks are generally a pointless draw, and well-played Vamps are tough as nails too.
Hell, Wardens can often embarrass any perceived OPd 1v1 class! I've had a sub RR5 beat my Minstrel with OJ pet on more then 1 occasion, because he buff-strips us both nekkid and thus makes the pet totally anemic...at which point it's a Minstrel dieing by "death of a thousand cuts." LITERALLY!
In open field Theurgs, in sieges Animists (still!), and in other aspects Healers CC, Shamies shearing, heck even the healing from the pure Healers can be described as being grossly OPd at times. Just depends on how you looks at it!
Many a duo/trio can beat double their odds or more, simply because one was a primary healer (or CCer) while the people they faced were a random mob of non-healing & no-CC classes. Sure feels OPd when you're with the group of 6 rag tag melees/rogues trying to futily beat up 1 enemy who is being healed by just 1 primary healer. A pointless undertaking really, basically no amount of meleers will out damage the primary healers heals, as long as the target isn't a caster.
In short, threads like this are generally useless. They only feed on the usually myopic and ignorant views limited to a specific play-style that the person voting is most fond of, while ignoring other aspects of game-play. Of course there are exceptions, the WL does excel at multiple play-styles and situations, and in general the idea of that much front-load DPS is purely stupid. (But even that is just my myopic, ignorant opinion cuz I have not actually played a WL! And wouldn't!

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