Soloed this guy on my level 36 necromancer. Dropped the bracers. Big upgrade from the ethereal cloth ones he was wearing. If you're wanting to try your hand at soloing him, you need a class with an interrupt or some kind of instant crowd control. He uses a channeled "Renew Bones" ability every 30 seconds or so when he gets low on health. I used my warrior pet's bash on command whenever I saw him casting it. It is susceptible to snare so it's pretty easy to kite. As long as you stay on top of interrupts it's not bad at all.
I tested this 3/7/26 and ... Yes, it actually DOES work. In fact I parsed higher than 15%, but that could be procs, the 4str on the item, or other factors beyond attack speed.
I used the lv50 dummy in Availia for 1 hour, in 5 min increments with/without.