Originally Posted by
Sageous
I, for one, have been regularly doing WBTB's for close to 40 years now, Germancho, and I'm fine.
With the exceptions Snoop notes above aside, I've never heard of WBTB's being bad for you, period. Getting up after several hours' sleep and going back to sleep a short time later is completely harmless... it might even be good for you!
Also, I always recommend doing WBTB's without alarms, because alarms tend to wake you up too much, which can hurt your lucid mindset, thus diminishing your chances of a successful WILD (they don't call them "alarms" for nothing, you know).