However I really would like to know if this is something that has been suggested within the airline to save fuel and time. Further to this, the same low cost airline only uses 1 minute cool down time for its engines rather than the Boeing time of 3 mins - sad I know but I've timed it!
It has
not been suggested by the company. This sounds like individuals going outside of the SOPs. I've spoken to a couple of guys, one of whom has seen it done several times.
The company also uses a 3 minute cool down period in it's SOPs as per the Boeing recommendation, one of the considerations for single engine taxi. So again. Sounds like people operating in their own fashion.