Hide explanation text by default

Have doubts about compliance - it doesn't appear to be an optional item. We might believe/hope that the audio recording contains a spoken record of the explanation. What if the staff member forgot? What if the donor was shown a card to read showing the explanation? I feel that it would be safe/clear to have a field that forces the staff member to check. It could be a bool, but that's easy to tick out of habit without checking. So the robust answer is to get staff to actually listen for the explanation wording.

I have wondered about things like this. For example, whether the declaration is valid depends on it having 5 key pieces of information, and an explanation, and evidence. One could imagine all kinds of UIs to get staff to verify the presence/absence of all the key ingredients and behind the scenes compute validity based on that.

However, the conclusion I've come to is that the right UI depends enormously on the particular circumstances of the declaration. So it's best left for sites that want this to set it up using custom fields/widgets on a custom declaration type specific to their organisation's workflow. As you point out, it's dangerously easy for any UI to be largely ignored by staff on autopilot, so it needs to be carefully suited to the circumstances.

What the guidance says is "in order for a Gift Aid declaration to be valid, the charity must give and be able to demonstrate it has given an adequate explanation to the donor of the personal tax implications associated with making a Gift Aid donation".

3 things of significance here:
- to "demonstrate" an explanation has been given sounds to me exactly like evidence, which we already have a mechanism for with the evidence field.
- in 99% of cases that evidence of the explanation will be the same thing (paper, audio recording, web form) as the evidence of the declaration
- the explanation could actually be on the confirmation email, so it could be missin initially

Therefore I don't think "explanation" makes sense as a base field on the declaration, because it's rarely necessary to treat evidence of explanation sperately from evidence of declaration & confirmation, and sites that want to do something more elabarate for a particularly tricky declaration type easily can.

For the 2 web self-declare cases, the explanation text isn't in the evidence, so we would need the bundle field.

Or we follow #3534245: Change handling of web evidence and additional evidence for the web cases to capture the explanation.

I don't really have a good sense of the best solution here, base field, bundle field or evidence. My slight inclination is to think bundle field is the right solution, because it makes it clear that the field is only relevant to those bundles that use it.

If the bundle field was configurable, maybe other declaration types could add it smoothly if it was right for them.

I had also considered that we could track the confirmation email wording or template version.

I think it would be a good idea to have a "confirmation email" evidence type that has the date sent, address sent to, full text, etc. and always capture that.