MrGaspo
I was using "symmetrical" to describe two parallel lines/tracks, but, sure, it isn't precisely the right word.
You seem to be of the opinion that it is a requirement to regain the inbound leg at the beginning of that leg , it isn't. This is explained in your reference to ENR 1.5 3.2.1
No, I'm not of that opinion, quite the reverse. My point is that if you attempt to fly a parallel outbound leg and then fly through the inbound track because you have a large crosswind component and a limiting bank angle, you no longer have two parallel tracks as the track to regain the inbound course will no longer parallel the outbound leg you just flew. It should be obvious that the inbound tracking is more important than the outbound, particularly if you end up never regaining the inbound track before you get to the fix or beacon. Common simulator scenario.
I was looking at the problem more from the point of view of jet speeds and bank angles, as the altitudes we fly at are more likely to produce the crosswinds I was describing, and also produce a more limiting bank angle. However, the principle is the same for light aircraft.