Indy Jess John formulated on Wednesday :
Normally the second LNB feed allows you to view one channel while recording
another. With only one feed, you should be able to either view or record,
but not both at the same time.

Not saying you are wrong, but I seem to remember my sat receiver with
single LNB input, allowed watch a channel and record another, providing
they were on the same mux(?)..