Not necessarily? In the current, vanilla state of the game, Spaz covers the greatest distances and Jazz & Lori are pretty much even. Lori's properties could be set so she can't jump higher than Spaz would with a double jump and, perhaps, slow her movements down ever so slightly so far greater distances can't be reached. Like an in-between character of Jazz and Spaz, not outclassing either of them but making her a valid character choice (Let's be honest now, who picks Lori while playing SP? You'll most likely end up realizing that one of the jumps is simply not doable and then use JJMORPH to continue).

On the other hand, I would much rather have the JJ2+ option to choose whether I want to play as a double jump character or a helicopter ears character (I already posted this suggestion in the JJ2+ suggestions thread). I'm a SP enthusiast, I just want to be able to take Lori into consideration when starting a level.