See, I think that is specifically in contradiction to what Norm 22 is saying. (Actually, Norm 22 is now Norm 18 in the 2002 (latest?) edition of the
Enchiridion Indulgentiarum.) The norm states:
Ut vero subiectum capax eas lucretur, habere debet intentionem saltem generalem eas acquirendi…
In order that a capable subject may actually gain it, he must have at least a general intention to obtain it…
Filling in the pronouns and what-not, that means: “In order for the person who
can gain an indulgence to
actually gain it, he must have at least the general intention
to gain it.” You must have the intention to
gain the indulgence,
not simply to perform the work related to the indulgence.
This is also found in Canon 996 §2, and in the old (1917) Canon Law as 925.
From
this commentary on Canon Law: “it has been usual to recommend to the faithful that they have to have a general intention of gaining all indulgences available to them…” (p. 1177)
Also see
this comment: “Also,
you have to want and intend to obtain the indulgences. This is why it is so important that we all be aware of indulgences–and believe in them! If, after reading all this, you decide you just
don’t believe what the Church teaches about indulgences, well, then you’re
never going to obtain one. And that would be very unfortunate.”