Should I send a live-stream to Lightcast from my live-encoder, and another one to a social networking site directly

We do not recommend to send multiple live-streams to different sites/services from your live-encoder, as it poses the risk that social networks consider them duplicate streams, which can potentially lead to the abortion of a stream on their websites. 

Instead we recommend to send one stream to the Lightcast Media Cloud (or multiple bitrates, which will then be muxed into a bitrate-adaptive stream in the Media Cloud), and have the Media Cloud distribute your live-streams to all your websites, social networking accounts, mobile apps and TV apps. This is the safest, most professional, cost-efficient and time-efficient way of live-stream distribution to multiple websites, social networks, apps and platforms.