I would ignore that advice, and stick with the routine you are used too - which is correct. Apart from anything else, the tr needs a few seconds to search and lock onto the channels it will use.I usually wait for these few seconds before switching on the receiver, otherwise the receiver apears to be "dead".
Faulty set...I doubt it. Fly with one or both receivers flashing? ..probably lose signal at one receiver at some point.
Of course, for all we know, we may be doing so anyway, 'cos I for one have several installations where it is not possible to see if both lights are solid without airframe surgery
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