If the OP is indeed taking a class, and found that in his manual, then his manual is not current and the class is not being taught to standards.
But if he is reading an old manual, c1994 (version 1), then on page 155 it says to drop weights and/or inflating your BCD. The next version of the manual I have in my library is 1999 (version 2.1) and it just says (p159) to drop your weights. And the latest version, 2013 (Version 3) agrees, ditch your weights (p161) to get buoyant. Note that the old option of "buddy breath with a single regulator" no longer exists in Version 3. So now there are only four ways taught to get to the surface: normal, your buddy's alternate air source, CESA, and emergency buoyant ascent.
I can't find the thread, but there was one on this topic maybe 4-5 years ago. I sent an email to PADI HQ for an explanation, and they referred to new (then) wording that was more ambiguous about the depth. When I give the exams now, though, I don't see that ambiguity. I really think they want you dropping your weights past that depth. They want to make sure you get to the surface. Yes, you should be able to do a CESA from 100 feet or more, but if you drop your weights and flare, your ascent should not be ridiculously fast, and the CESA skill of exhaling the whole way is still in effect.
As for the wording of inflating the BCD when you are out of air, remember that this section of the course is for low on air and out of air emergencies. The first option is the normal ascent, breathing all the way. in that situation, the BCD could be inflated, although that is not the ideal choice and probably the reason it isn't mentioned any more.