After 5 months when I set the question:
now I can say that the working, fully functional prototype of SAP ERECRUIT can be built very fast: 5 months by agile approach by on-promise, and even 3 or less months from box in the cloud.
Because of troubles with the system we were forced to work in the “waterfall” way. The fact are: 1 month for analysis, about 3,5 for blueprint (including Christmas) and after the next 4 months we went live in July. All together almoust 9 months. Now after 3 months we have stabilized the solution – more or less since we are still making roll-outs.
From the today’s point I can say that SAP ERECRUIT is perfect example of standard software that can be implemented incrementally and very fast. Even the SCRUM method can be used – of course under some circumstances what I will write about in separate article.
In my opinion the most effective way of SAP ERECRUIT deployment is to deploy the RDS package and then to play with two or three prototyping time-boxes. From today’s perspective four months together for analysis and blueprinting were waste of time or even some kind of trap.
The optimal way of deployment is standalone scenario – because of many reasons named in many articles so I will not replicate. And SAP ERECRUIT is working very well that way. Even having SAP ERECRUIT hosted by different vendor as the rest of IT landscape incl. SAP ERP is working seamless – that means SAP ERECRUIT may be excellent package for complete outsourcing or offshoring – as SaaS as well especially because of heavy personal data protection aspect.
The main problem by the of RDS is plenty of integration work, activations of business functions or similar activities – in short worlds the deployment of standard is not easy. My rough calculation is that even 30% of the consulting services (all together about 150 days) were consumed by this type of activities. It means that SAP ERECRUIT may be perfect product delivered as the box in the cloud – it means ready to run RDS. In that way I can imagine that even 3 months (and about 50 days of consulting services) would be more than sufficient to have working recruitment system from the “buy” decision.
The big issue are smart forms (layouts of requisitions and mails to candidates) and that that may cost a lot but with proper organization it can be made smart and chip as well.
And last but not least: for SAP ERECRUIT the two layer deployment architecture is fully sufficient.