In the case of the latter, the pilot of the 109 would not be able to see the Spitfire at the moment he leaves the inside of the Spit's turning circle and enters to the outside.. it would be a momentary blind lead situation, and he'd have to guess the timing where the Spit that entered under his nose would pop out from his left 9~11o'c corner to continue with maneuvering. This takes a lot of anticipation, and experience is required to pull such a maneuver off with confidence.
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In many simular situations a lot of blind lead is involved. Typically when you are aiming at a more maneuverable enemy. Because the enemy is not dumb, and will most definately enter a turn to get out of your gun sights, there is rarely a moment you'll get to see the pure 5, 6, 7o'c angles of a plane like the Spitfire. Most of the times you'll see his top side.. and in chase like this you'll rarely ever get a chance to fire at a lead angle where you will see your target. Because poorer turning planes will almost never be in a situation where he would be able to out turn better turners(there are a few special situations where this is possible), the best chance you have is to follow the lead path steady, and at the moment of truth, you pull the plane so it enters blind lead and fire a burst that is longer than snap shots, but shorter than tracking shots.
This also needs a lot of experience and practice, and the "feel" needed for these type of shots vary on one's condition. In a word, unless you have specific advantages where you can see the plane you are aiming at, in a poor maneuvering plane you'll have to deal with blind lead shooting any way you can. In my view it is about 50% luck and 50% skill... and the parts that are not governed by pure luck can be made up by practice, and planes that are suitable for such gunner - such as planes armed with Hispanos cannons or .50 machine guns.
