Indeed. If you played Battle1 a lot during your JJ2 lifetime (and you most likely did if you played in the old days) you would at least came across the Blaster Powerup once. And it's also pretty common that by carefully playing the single player as Jazz, you would at least spot the powerup sitting on it's location (whether you actually reach it or not). And then anyone who completed a full-scaled level in JCS should've noticed the powerup in the list, or even placed it.

Yeah, I can't call this powerup a mystery even to non Jazz fans..