Well, Gemp is clearly incorrect about applying one rule to
Hearken to Me /
Shadowfax GotM and another to Watcher
MTC. That's clear. But now I'm dismissing my own previous post, the whole "continuous ONLY IF says while" idea...
I believe now that
Hearken to Me must be continuous. I was writing a fancy detailed explanation about why
Hearken to Me must be NOT continuous just because doesn't say "while you can spot this card" or "while this condition is borne by Théoden"... just to realize that
Saruman KoI does exactly the same: he doesn't say "
while you can spot Saruman, Uruk-Hai are fierce." Nor
Lord of Moria says "while you can spot this condition." So if effects could ONLY be continuous by having "while" written in them, Uruks would be fierce due to Saruman effect only during the phase he is played. Shadow phase only, absurd!
The text I quoted from the Comprehensive Rules document,
"While is used if an effect is continuous", rules over continuous "triggered effects". Well, either none of those 3 cards have triggered effects, or all are self-triggered effects: triggered by simply being there. Which makes the hypothetical "while you can spot Saruman /
Lord of Moria /
Hearken to Me" text redundant and thus unnecessary to write. That quoted text is followed immediately by an example:
"While Merry bears a weapon, he is strength +2." But
Merry FOtB cannot self-fulfill his own trigger. The trigger MUST be written in that case; and uses "while" to differentiate from "when" and "each time" (non always-self-fulfilling) triggers.
TL;DR yeah,
Hearken to Me is bugged and should discard
Blade Tip. Phallen Cassidy was right.