This looks like a legitimate request and it's worth an analysis.
Originally, I wanted to continue with a long argumentation on how the blocks are necessary for correct event displaying, that it's necessary to align the blocks with the cells, and that it would be mixing of two different purposes.
However, it seems that the blocks are useful for really short events where they force them to become bigger and better readable objects (otherwise there could be events 2px wide). But for the longer events, it's actually not necessary and it's doesn't mean any UI improvement.
I will need to extend the current set of options for UseEventBlocks (Never, ShortEventsOnly, Always) with something like Custom. It will also require other API extensions (I'm not sure it should be available on the top level along with DataStartField, etc. - it will rather go into BeforeEventRender). This is not quite trivial so I'm not able to provide it within days. A realistic schedule is somewhere around 1 March release (
4.6).