The only gels I can handle on a bike are the chocolate ones, because the consistency feels more natural than if i were eating a gooey fruit one.

Also, the benefits for gels on a bike are that you can tape them to your frame in such a way that you can just rip off the gel and the tab stays taped to your bike, then you just suck and don't lose speed as you do it. I would imagine it'd be hard to fiddle with the shot blocks and bags.

K.