4 Way Splitter vs. 8 Way Splitter

I just had whole home DVR installed at my house and the local installation team did not have the equipment needed to do the install.  As a result, the technician used a 4 way splitter instead of an 8 way splitter.  I have 3 HD-DVRs in my home.  He advised that local management told him it would work.  The technician advised from the very beginning that he did not believe it would work but when all was said and done it appears everything did work.  I am able to see my playlists in each of the three rooms where I have HD-DVRs.  However, I am now worried that I am losing some sort of functionality.  Why is the 4 way splitter working when I was told I needed an 8 way splitter?  Am I missing out on any features b/c of the use of the 4 way splitter?  Am I going to have any issues b/c of the 4 way splitter that was installed?  Do I need them to come back out and install the 8 way splitter?  

Thanks in advance for the feedback.