From our instructions:
Daisy Chains are variable length tie-offs designed to support body weight ONLY. DO NOT use them as part of your belay or protection system. They are NOT designed to hold falls.

Warning: Improper use of Daisy Chains can cause severe shock loads. When clipped to an anchor (or other piece of gear) with a Daisy, never climb above the anchor (illustration 5). In the event of a fall, the Daisy will not stretch, resulting in a severe shock load to you, to the anchor and to all gear in the system. This can potentially injure you and can even cause your gear or anchor to fail.

Another very real and very dangerous issue with using daisy chains is clipping in short. If you incorrectly clip in short to a daisy, it can be potentially bad. Very bad. The thing to remember when clipping in short using a daisy is to use a SECOND carabiner to shorten it up.

From our instructions:
Always use a second carabiner to shorten your daisy chain

Im Grunde ist es möglich, dass wenn du eine zweite Schlaufe oder Tasche an deinem Daisy am Hauptkarabiner befestigst, der an der Endschlaufe deines Daisys hängt, das Endergebnis darin besteht, dass der Karabiner nur an der Spitze der Tasche eingeklemmt ist und daher wirklich, WIRKLICH schwach – nämlich mit einer Zugkraft von nur 500 Pfund. Unten siehst du ein Video, das die Gefahr deutlich zeigt. Vielleicht musst du es ein paar Mal anschauen, denn es ist ziemlich verrückt, und nein, ich bin kein Zauberer.

Basically, it's possible that when you clip a second loop, or pocket of your daisy, to the main carabiner, attached to the end loop of your daisy, that the end result MAY really be the biner just being clipped across the tack of the pocket, and therefore being really, REALLY weak—as low as 500 pounds. Below is a video that clearly shows the danger. You may have to watch it a few times, because it's pretty freaker crazy, and no, I'm not a magician.

NEVER clip a carabiner in to more than one pocket at a time. If the bar-tacks between the pockets were to fail under load, you would no longer be clipped in! This scenario could occur when any two pockets are connected to a single carabiner

Bottom line: Daisy chains are for aid climbing NOT for use as part of your personal anchor system. Don't know how to properly anchor yourself using the rope? Don't know how to thread sport anchors without clipping in with a daisy chain? Then go get some instruction from a professional guide IMMEDIATELY before you get yourself hurt. If you're aid climbing and going to clip your daisy in short, it's always best to use an ADDITIONAL carabiner to clip to the main carabiner thus avoiding the potential loading scenario above.

Be safe out there,

KP