its far from the exception. a vast majority of kills were diving onto someone's unsuspecting tail or the target of opportunity zooming past your nose giving you a great deflection shot or the chance to climb on his tail. but when the battle lasted past the point of surprise it usually went either horizontal or vertical.
most of the time full throttle or going through the wire (WEP) was used was to bug out or when the ea broke for the deck ( which was common practice ).
plus it all depended on where you were....eastern Europe and western airwars were vastly different. and the type of the plane you were flying dictated tactics. german pilots were told not to get into a turning battle with most soviet ac.... so the luftberry circle they employed in the west was of little us to them over russia. hence it was somewhat common.
here's 2 pages of encounter reports of 51 and 47 pilots....
http://www.wwiiaircraftperformance.o...t-reports.html
http://www.wwiiaircraftperformance.o...r-reports.html