[ecesena]

It varies at different stages of your company. You should measure where time is wasted and optimize.

If you're doing A) and you get a ton of clearly unqualified candidates, you want your dev team leads to do the initial assessment and the recruiter(s) to learn from that.

If, viceversa, you're doing B) and your dev team leads are spending most of their time recruiting, then you need to smooth into A).

As a good rule of thumb, during hiring season, the dev team leads should spend around 30% of their time on recruiting, not more than that. Less is always good, of course, but it shouldn't come at the price of wasting more time during longer interview cycles.