Yes it is very necessary. Not a stupid question at all, at least you took the precautions, most people don't. Listen at under half volume for about 20-40 hours and that should be enough to loosen the suspension and burn off excess glue, etc.
i agree, very interesting. many sub manufacturers recommend break-in by pushing the suspension to full stroke for several hours. i wonder what is it about smaller drivers that makes them so much different?
A lot of subwoofer manufacturers recommend less than half power as well. The reason is that excess glue, etc. may still exist on the voice coil, which will have to be burnt off. With the glue in place, there is less thermal handling since the glue will retain more heat, it could possibly damage the voice coils. It doesn't really take full power to break in a driver, half or less should move it enough to loosen the suspension, and also burn off any glue.
I usually use a gradual approach to it, under half volume for about 40 hours (I'm not really an SPL guy anyway, I usually listen at those levels anyway) and then gradually push it closer to full potential.