Rick,
Your first example isn't a fan. The tape starts a bar earlier on that one.
On the second the fan my be more because of the decreasing volume BO, vs taping to a decreasing volume bar.
Some thoughts on tapes: They are our smallest containers. When we see a VE of a channel we adjust and accelerate our traverse. Same with the tapes. Even with lower volume we still annotate a steeper tape that accelerates or extends. Since we are using bar ends (tops and bottoms) to draw them initially, why redraw a new tape if the bars are mostly contained in the tape? Waiting until the close outside a LTL to redraw appears to be a way to tape without adding too much clutter by drawing every 2 bars, and dropping to a bar to bar fractal level.
Regarding the fanning, say we are taping a dominant move. We would try to tape to an increasing volume bar if possible. But with a low volume bar we might need to fan to get there. For example moving out of a sym pennant, where we might use bar 1 and 3 for the tape. Sort of like fanning our channel on a FBO.
The pennant example I gave doesn't jive with the pennant in your example, but occasionally I see some other ways pennants or flags are taped. See the attached for an example cut from Mr Black's recent pic.
