The simple truth

[Esquilax]

I'm not sure I agree with that.
Take, as a metaphor, the conversations I've had with smokers. From a professional point of view, I know the damage it does over time and indeed from a personal point of view how hard it is to quit.

When I was doing hypnotherapy, one had to find the "corner" to pick at to motivate people to stop. For some that was improved sporting performance. For others it was improved quality of life, or health, or financial or one of a dozen other things. One had to gently probe to find what was important to that person.

What you DON'T do is walk in the office, slam a picture of a 35 year old cancer victim on the desk and ask the person why they are so fucking selfish they're going to put their kids through the pain of losing a parent before they grow up. Not until you've tried everything else at least.

Regardless of the core belief, there are ways in which a message can be delivered which are more, or less douchy

While I agree with your principle, I find the way that christianity seems phrased to that kind of christian renders the option of being nice about it kind of impossible. To the "we're all worthless sinners!" christian, salvation isn't about helping people to the best possible outcome, it's almost a case of debtors and debt collectors, where god is owed worship, and anyone not doing that- in exactly the same way!- as that particular christian, is being delinquent on a substantial debt.

It's not a case of helping anyone, it's a case of bringing in a criminal, almost.