Do bonuses to attack stack with bonuses to dash-attack?

You can receive various bonuses to attack, special and cast from boons. But you can also get some boons that provide a bonus to dash attacks specifically. How exactly do these interact with each other?

• is the dash attack affected at all by bonuses to attack (and not specifically dash attack)?
• do they stack additively?
• or do they stack multiplicatively?

Did a bunch of testing in Tartarus using the eternal spear with mirror of night bonuses off, Artemis trinket (since only her dash boon affects dash attack), companion Rib to use as a test dummy (gave up on that quickly, fun fact! you deal drastically reduced damage to Rib's Skelly). Here are my findings:

Firstly, what is a dash attack? Its an attack made while dashing (lol) this however has numerous implications. Dash attacks benefit from any and all boons to attack, +40% attack boon causes the dash attack to deal +40% base damage although dash attack and regular attack may have different base damage values (Varatha standing 3 hit combo does 25, 30, 30 damage respectively but its dash attack does 20 damage). Dash attack also applies all on-hit effects of the attack boon so dash attacking applies Dionysius' hangover, Ares' doom, etc.

Secondly, how do multiple instances of bonus dash attack and attack damage stack? It turns out to be quite simple, it's all independently additive. I collected Artemis dash (+70% dash attack), Chaos dash-attack damage (+58% dash attack) and a Poseidon attack (+44% attack) boon which sums to an increase of +172%. The actual dash attack dealt 54 damage which is consistent with 20 + 20 * 1.72 = 54.4. Doing a fair bit of trial and error with the arithmetic no combination of multiplication with the bonus values seems to result in the same value so it seems pretty cut and dry and I imagine this is how multiple damage bonuses work for any damaging ability.