Effects Preventing Extradimensional Movement Stop the Rope Trick Spell

The spell rope trick [trans] (PH 273) creates an extradimensional space. Entering that extradimensional space requires climbing up a rope. Crossing from the rope to the extradimensional space is an act of extradimensional travel.

Extradimensional travel has a variety of hard counters, even in core.

• The 4th-level Sor/Wiz spell dimensional anchor [abjur] (PH 221) grants the caster a ray that, if it hits, for 1 min./level stops the affected creature from using extradimensional travel. As a ray, it requires a ranged touch attack, and not!Sauron probably has defenses against those (e.g. ray deflection [abjur] (SpC 166), miss chance).
• The 5th-level Clr spells hallow [evoc] (PH 238) and unhallow [evoc] (PH 297) can be cast so that they ward an area with an effect like the spell dimensional anchor for 1 year.
• The 6th-level Clr spell forbiddance [abjur] (PH 232) permanently wards an area versus extradimensional travel but the caster can makes allowances for their buddies.
• The 8th-level Sor/Wiz spell dimensional lock [abjur] (PH 221) for 1 day/level wards an area versus extradimensional travel.

All of these stop the wizard from entering a rope trick; none force them out of an in-place rope trick. Even if the DM disallows dispel attempts on the rope trick proper, the trick will expire eventually, and then it's a game of rope trick leap frog to catch not!Sauron if they've devoted enough resources to this tactic (which I applaud, by the way--how cowardly and underhanded!), even moreso if they're out in the open (which prevents forbiddance and hallow/unhallow). That's okay. We're talking a high-level person who's devoted their resources to the spell rope trick and literally holing up, and that's weird.

A high-level person teleports away--they don't rope trick. A high-level person goes to their backup Batcave on another plane--they don't rope trick. The only reason they continually use rope trick is if something they want is nearby. That becomes the adventure: there's a reason not!Sauron chose rope trick--which in most cases is vulnerable and which everyone knows they can wait out--over just straight-up leaving. Find what they want, and threaten the wizard into a (semi)fair fight.

The Question's Scenario

Day 1

• Surprise Round: The rope trick spell ends. Assuming not!Sauron's maneuverability lets them hover, they use the surprise's round's standard action to cast rope trick.
• Round 1: not!Sauron wins initiative and takes a move action to climb the rope into the rope trick. Then they take a move action to retract the rope. Combat ends if the DM disallows dispel attempts on the rope trick.
• Remaining Day: The PCs go into town and buy a staff of dimensional lock (8th-level spell at caster level 15) (300 gp + 1,800 gp/charge; 4 lbs.). They use 1 charge on the area where the rope trick was cast.

Day 2

• Surprise Round: The rope trick spell ends. Assuming not!Sauron's maneuverability lets them hover, they use the surprise's round's standard action to cast rope trick.
• Round 1: not!Sauron wins initiative and takes a move action to try to climb the rope into the rope trick; they can't enter, prevented by the dimensional lock. They take a standard action to cast a spell, possibly eliminating a PC. The PC with the staff readies an action to activate it if not!Sauron casts a spell that the spell dimensional lock can prevent (an individual DM's interpretation of the ready action may vary). Remaining PCs attack wizard.
• Remaining Rounds: Fight!

This scenario is vastly simplified and ignores infinite variables, but it's to show the means above in action.

Description of each rod states:

The wielder can cast...

Meanwhile, to wield means:

to use (a weapon, instrument, etc.) effectively; handle or employ actively.

More definitions, all pretty similar.

The Magic Item Compendium seems to clarify it even further. Activating Magic Items section (p. 219) includes this sentence:

A rod or wand must be held in your hand

Also, each rod described in the compendium (including metamagic rods from sources other than DMG) has the following entry for "Body Slot":

-- (held)

For some softer arguments

Take this sentence from the confusing "Use-activated" section in the SRD:

Use activation is generally straightforward and self-explanatory.

Obviously it is not for rods, but it should. Substitute "rod" with "scepter" (because Rods are scepterlike devices) and it may become more clear. "Using" a scepter is probably a bit more self-explanatory - imagine a king holding a scepter hidden under his cloak.