I presume that in many radial engine aicraft the front visibility mostly at take off would of been horrible and with a aiming device just on the middle of your front shield.. Almost all the pilots positions in DCS, IL2, RoF are wrong... and can be corrected.
In modern days Yak9U for example we used to take them off or not even mount them.. the pipper was smaller than in the German aircraft and it was very annoying. they do look good dho.. but landing in modern airport and taxi, traffic etc.. it is a "pain". you open the canopy and start your zigzags with a long stretch neck ;)
Here a little crude view .
But I may talk out of my a** right now since I do not know the plane..