turn signals in middle of trailer/5th wheel?

Has anybody installed turn signals in the middle of you towable RV? Do they help??? Any hints?

I notice many times a car will let you in or get out of the way when they see your signals. But that is when they see the signals. For someone along side you, it's hard for others to see your blinkers of tow vehicle and they can't see blinkers at end of your towable.

Of course others seeing your signals and doing something is another subject all together. Just trying to up my odds of more visibility.