Yeah, just the other day doing my base check, I asked a check and training captain his thoughts on this procedure..that is straight after landing, feather the engine to slow aircraft down instead of using beta.
His answer was that it does slow the aircraft down without causing much noise (that is the noise created with the use of Beta), plus beta causes no cooling whatsoever!!! and therefore thinks it ok to be used!!
Only place i have seen this procedure used...mind you I will stick to using beta while taxiing. Nothing in the SOPs about this procedure (that is feathering after landing)