Narin might have been exaggerating a bit. The only time that it's possible to brick is if the DS is turned off within the first 3% or so (and in fact I've heard of a couple stories of users recovering after the DS turned off at 1%). This is literally within the first second after you successfully short the SL-1 contact. After this mark, you will be able to recover if anything goes wrong, as the recovery code is the absolute first thing written to the firmware.
If the DS is bricked, you can use the BIOS swap method (which conveniently requires two DS Lites) though this would require you to open up the DS systems. With this, you start FlashMe on the good DS (no risk here since you don't press XBXB to continue yet), swap the bad BIOS into it, and then continue the FlashMe installation. Much easier than the method that requires soldering and cutting traces. Furthermore, if you don't feel like doing it yourself, you can contact bitblt on the SCDev forums, a reputable forumgoer who will recover your DS for you for a small fee plus shipping charges.
In essence, as long as you're safe and don't touch the wrong contacts, you should be fine. There is a small risk of bricking which you do have to be prepared to accept though.