which is a better measurement of a PVP guilds overall skill?
1) A 5 on 5 Mage Duel on Wrong roof (books Equipped & only a Magery spellbook in your backpak)
OR
2) WARRING each other & having the "SCORE" speak for itself...?
5 v 5 mage w/ book it hand (#1) would be best with no items as you suggest, no fields, summons, strangle, maybe not poison either, no paralyze, no sleep, generally no curses other than to disrupt (weaken, clumsy, feeblemind), would probably be an interesting way to determine the best twitch players, but I'd assume a lot of these groups would settle for meteor/wither/fields.
Duelists generally frown on anything outside of magery spells in a duel, which does limit most of the templates that exist today, but it also takes away most of the RNG which dilutes any way of measuring "skill." In that case, what is a 5 v 5 mage duel? 10 mages w/ wrestle and inscription (any scribe mages left)? Or would both sides agree, Mage/Eval/Resist, no movement as to avoid the use of wep/wres/parry, single target direct magery spells only, no curses other than 1st/2nd and no additional skill usage outside of passive skills like med and focus?
Traditionally, though, duels are best when 1 v 1 ... a 5 v 5 duel in a set area or environment, such as a champ spawn, or better yet, a harrower (#2), would be the most realistic way to determine a PvP guild's skill. Harrowers are pretty much the most important part of the game, imo, although, some of the templates people run for factions, the niche templates, are pretty specific, and maybe then sigil protection is even more skillful than a Harrower, except, a Harrower is arguably much more valuable than a town in the short term.
I think the bottom line, from this discussion, is to find PvP skill, the situation has to be artificial. Any skill/spell/etc that uses RNG cannot help determine "PvP skill" because the variance cannot yield accurate results, which is why people have, since forever, relied on Mage Duels to indicate user skill. In the case of a dexxer fighting a dexxer, why fight when all you need to do is stand next to each other, have one person flag, then see who the RNG picks to get the hits in first.