Lasty, perhaps I overreacted; looking back, I see that you didn't actually disagree with every single item I listed, but only with a selective majority of them. I thought you were just busting my balls but maybe you were interested in specific points.
If you want to talk about the specific items you cited, I'm game.
I disagree with these. Lignification is very strong for many characters through the end of the Lair branches. Low-level attack wands lose their usefulness fairly fast but can still take down a hydra. Noise I mostly drop, but can be useful to break mesmerization in Shoals. Polymorph is useful for the many low-MR, equipped enemies you run into, and vulnerability can make most enemies low-MR, both of which you illustrate in your Royal Jelly example. Berserk/Might/Silence are all very useful on a DEFE unless you go for the "can't touch filthy weapons" glass-cannon challenge condition.
You know my thoughts on lignification. Noise could be useful in shoals except that usually I find a wand of lightning which does the same thing and has more shots. Nothing about dropping an item says you can't come back for it later, when it's time to do shoals. Personally, I don't use polymorph much except for TRJ, but yes that is a strategic option one could exploit. However, confusion or paralysis is usually at least as good, if you're facing an enemy whose MR you can overcome, so I usually carry that instead. Vuln is so rare that I usually save it for TRJ instead of using it up on earlier enemies, so I don't carry it.
Berserk/might/silence are all theoretically useful on a DEFE. However, berserk should only be used if you are quite confident you can overcome all opponents in melee while berserked, which is rarely the case with a DEFE by the time you're worrying about too many inventory items. Even for most berserkers, berserk should be used less as the game advances through vaults and depths, due to the danger. Silence is very rare, and useful even more rarely, because in a time of danger it cuts off many options for escape and damage dealing, especially for a DEFE. It's not that it's useless, it's that the inventory slot could be better used for, say, a blowgun. Nothing stops you from picking silence up again when it's time to face the aliches in zot5. Might is more generally useful on a DEFE, but most of my mages haven't had that much occasion for might. It's not that they don't fight with melee, it's that they prefer to melee the weaker enemies where buffing is not necessary. So with me, on focused mages, might tends to eventually get bumped in favor of other items.
I strongly disagree with these. Attack wands do reasonable damage and allow you to reach targets you might not be able to otherwise reach throughout a full three-rune game; advising people to drop them by mid-Lair is really bad advice. Scroll of holy word isn't often useful, but when it is it can be a life-saver, particularly in regions with liches. Potion of cancellation removes a variety of dangerous statuses like slow, mark, petrifying, dimensional anchor, etc. Scroll of immolation really depends on the character -- sometimes they represent the best (or even only) way to get out of a bad situation; generally I'll start dropping these late game once I have enough other tools. Stone of tremors is definitely the worst elemental evoker, but it's far from useless, and now that evokers stack it's less often that you want to ditch them. Ambrosia allows for incredibly quick mp/hp recovery between encounters, which comes up fairly often, and early in the game heals you fast enough to outpace most sources of incoming damage.
I didn't advise people to drop attack wands by mid-lair, I said to do so if you aren't going to be training evocations. With high evocations, I later clarified that by the end of vaults is when they tend to lose their punch compared to other evocable items, not mid-lair. At 0 evocations, it's usually just a waste of a turn to use an attack wand in lair branches and beyond.
The items in this section were those that I said can "often" be dropped. They're all useful in some situations, so you don't want to drop them unless you're cramped for space and need to make compromises. But that happens. Would I rather carry a ring of fire resistance, or these potions of cancellation? I'll take the rF+. How about this ID'd legendary deck of escape, or this scroll of immolation? Escape please.
- Why would you be cramped for space? Well, maybe you're carrying a blowgun and curare/poison needles, or some throwing ammo, or several different weapons that have different resistances or damage types which you switch between. Maybe you found a few good rods, or a few different magical staves. Maybe you have a ring of teleportation or amulet of rMut that you aren't wearing, in case you get abyssed. Maybe you do have evocations and are using attack wands (for now). Maybe you want to keep a few inventory slots open so autopickup works without annoying you during autoexplore. I suspect the real difference between us is that you carry fewer of these non-consumables than I do. But the case can be made for their usefulness.
Wednesday, 31st December 2014, 13:28 
here, and mention that trees cant quaff potions? Or did they change that..