You are better off in that scenario doing 2 PS combos then using DA for souleater.

Effectively each mana gen is roughly 1/3rd of a DA.

So you lose 1/3rd of a DA's added damage by doing another PS (so 40 potency).

And then you lose a delirium's combo vs ps combo worth of damage (10 potency).

...so you lose 50 potency total...while getting more threat, while gaining vs potency lost from using DA PS vs DA SE, which is 120 potency.

Much better to never, never use DA PS. Only situtation I see is if other tank dies, provoke off CD, and you need to immediately rip a target.