Ah, yes. The in seat rest. My last airline introduced this as it was allowed by the relevant aviation authority. The company said that 'cat napping' was allowed. On receipt of this information, I decided to observe my own cat and came to the conclusion that 'cat napping' involved sleeping on top of the central heating boiler for 21 hours out of 24!
But seriously, when it was introduced, from my own experience - three times in two months, both of us were woken from deep sleep by the 20/21/22 minute (Boeing) alarm. ASRs raised, but no interest from the relevant authority.