In all honesty the eicar test isn't about security, it has no bearing on real life protection, it is an artificial test to trigger an alert to indicate that your AV is running.
Yes, it is true. But since the manual scan detects it, why not the real time projection?
I think that you have had your answer in the two quotes by Vlk and igor posted by NON.
The manual scan is essentially the highest level of scan, it scans everything even files/stuff that presents no risk at all.