Although this was not asked it is a related issue---
the minimum speed that must be achieved for the third segment is 1.25 Vs [US FAR 25]
so minimum acceleration is from V2---1.25Vs...with the required gradient specified by Old Smokey---He could write a 5000 page textbook titled 'Airplane Performance'
Vsplat, "here is a common belief that analyzing a departure for the one engine inoperative case guarantees SID climb gradient compliance. Not actually true" ----
--- In the US what you said is so true because the departure tracks may differ because unlike some countries; in the US OEI performance is not considered in the departure track all engines is assumed--but as you stated every country does TO Perf differently
