With an SVideo Y splitter 1M 2F, does the video input need to go in to the male end?
Analog cables are thin bits of metal with connectors at each end. The signal that comes out of the source is present instantly* at all of the other connectors whether they are male or female.

However, connecting two outputs does change the impedance that the signal is seeing. Since you're dealing with an analogue signal, where the amplitude of the signal directly relates to the brightness of the image this could cause problems. To oversimplify it, it's like you had a battery and two light bulbs connected in parallel: they're each going to be less bright than a battery connected to only one light bulb. 

So where possible you're better off connecting one source to one input. To split the signal use the output from the equipment, as it will be buffered by an internal amplifier.

*ignoring the time it takes for the signal to propogate which will be based on the electomechanical properties of the wire, but will probably be better than 0.5c (where c is the speed of light), or in other words for a 1 metre cable the signal reaches the end ~ 6.7 nanoseconds after it appears at the other.