''But can Tsukushi stop messing things up'' is a pretty sobering question (^^) The girl has a heart of gold and she genuinely cares, but she's definitely a bit of a dumb-dumb.
To be fair, she has Hinoka as her girlfriend, who is incredibly competent at achieving her own goals. The sole reason this story is so long is that Hinoka also enjoys handicapping herself for funsies, like deciding that she won't confess until her super-dense friend does so first.