Recordin offDVR,but haveto output video via dvdrecorder to tv,messing with recordings

ok i just got a jvc dr-m100s and i am starting to record the video from my comcast motorola dvr box. Now i have a problem setting up all these connections. The JVC manual said to connect the DVR’s output’s to the tv’s input and also to the JVC’s input. Ok i tried that and the JVC’s menu, display etc. does not show up on the TV.

So here is what i have to do :

Connect the DVR’s output to the JVC’s input and then connect the JVC’s output to the TV’s input. And this lets me watch, record tv and see the menus on my tv through the JVC’s output and input.

As i am not to familar with dvd recorders, i just have a quick question.
Ok since i am not hooking this unit up as the instruction manual says because it doesnt work, and since the JVC has to recieve the video from the DVR and not only record it but also output it to the tv, does this mess with my recordings?
I watched a recording i just made and the video doesnt seem to skip or anything bad, but what about the quality? i dont have nothing to compare the quality, so would this setup mess with the quality(considering the jvc has to do two tings at once with the video it is receiving from the dvr?)