It's not too early for bulbs

This is a nice "how-to" for forcing bulbs.  I haven't tried it but it sounds quite simple.

If you are considering forced bulbs for your own home or as gifts, now is the time to get started. Preparation is key to success--the rest is easy.

Think of this process as "fooling" rather than "forcing." The bulbs have to be fooled into thinking that they have been underground for a cool few weeks, before they begin to sprout and bloom. Timing varies according to species, but even the fastest worker needs at least 10 weeks to chill out. Exceptions are Amaryllis, and the Narcissus Paper Whites that need only about six weeks and do not require a cold period.

I was intrigued by this tidbit:

Don't expect too much from this bulb. Once fooled, bulbs learn and are cautious. They might bloom again, but with less vigor, if only to provide you with a little color and a happy memory of former glory!

Is this true?  Do any readers out there know why?

Link: Exeter News-Letter Community News: It's not too early for bulbs.