Splitting the signal like that will likely yield some signal degradation (the signal received by both the DVD-R and the VHS will be weaker than they expect), which will probably give you less than optimal recording quality. I'd tend to suggest connecting one of them to zone 2 instead. This would mean that you would have to activate zone 2 and set it to the input you are interested in recording before you start recording to whichever one you hook to zone 2, but it also means you could be recording through zone 2 while watching some other input entirely.