I watch to see -some- oil pressure rise.
As long as it moves up, even a little, I'm OK to watch and wait until the start completes.
If I see 0 oil pressure by lightoff, I'll abort the start.
If the Low Oil Pressure ECAM comes on after start, then I'll follow ECAM.
I've been doing this for 16 years on IAE 320/319s, and it's worked so far. I've had only 1 start abort related to oil. The ECAM low oil pressure warning came on after start, but the oil pressure indication on the Engine page showed oil pressure.
I shut it down and went back to the gate.