Somehow I was never aware/curious of this, it was just there because they need to be there(due to some regulations imposed by law). Brilliantly said by an engineer,
Every system on aircraft runs simply upon common sense
So according to him, M11 is easy because only a legit common sense loaded mind is needed for preparation. Hmm, do hope so.
The swirls on the engine nose cone is no doubt for the purpose of clearer indication but for whom! I heard a friend said he lol-ed hearing someone said it was there for birds to notice such and not to get swirled into the engine.
In fact, it is for sake of ground operations so that people working near the engine could notice that the engine is running even from distance.