Fan Speed and Temperature on MBP Retina 13 2013 I have a 13 inch MacBook Pro retina (bought new in 2013).

When running normally (which is usually online downloading and editing in Eclipse - nothing too heavy, often 90%+ processor idle) it runs fairly warm. To the touch it's hot in the top-left above the keyboard (where everything plugs in) and iStat gives the CPU temperature as between 50-70 degrees C (CPU Die, CPU proximity usually 2-3 degrees less).

I see from various searches this seems pretty normal for MBP and shouldn't in itself damage anything.

My question though is about the fans - they're always just plugging along around 2000 rpm.

If, using iStat, I set them to use a profile with say minimum 4-5000 rpm then, naturally, everything cools right down. With the default profile I get the temperatures above.

So, is this right? Presumably when I say 'default' it's using Apple's determination for fan speeds. But is it normal for it to get to 70-degrees or thereabouts without the fans automatically speeding up?

And as a supplementary question assuming it is working correctly in not speeding up for those temperatures; is it a good idea to perhaps use iStat to have the fans speed up when charging/plugged in (when it gets the heaviest use via Thunderbolt connectors)? Other than battery life being less my guess would be running everything cooler would give a longer life to components?

Many thanks in advance for reading my long and meandering question!
You should check the fans(s) in a MBP on a somewhat regular basis. There is a grid in the exit that channels the air coming out of the fan which tends to plug with lint. Remove the bottom cover of the machine and remove the fan(s). You will probably find a wad of lint obstructing the grid.