SC 练习题一问

Joplin's faith in his opera "Tremonisha" was unshakable; in 1911 he published the score at his own expense and decided on staging it himself.

the key is: to stage the work himself

My question is why the original phrase is wrong?

Thanx

1,decide on sth. not ' decide on doing sth', at least I didn't find and instance which uses the latter. But I am not sure as to this point.

2, stage the opera, not stage the score. An native American or English can readily recognize this fault, the logic meaning of A is rediculous.