It's not the most elegant path, but it's certainly there. Now that you mention this, I'm debating having both points open from the start, a la Gravel Pit (but I'm not sure if I would auto-cap A if B was capped).
If its placed like:
Then i would suggest That A unlocks D and B unlocks C. So there still remain 2 points open at once. Or once both A and B are capped C and D get unlocked. However, the transition between having to defend 3 points, then 2 points and then agian 3 points might be odd on that last one.
And keep in mind it would make it very busy for red to defend 3 points. Early on it might not be a problem, but if they managed to cap both A and B then it shows they do have some pushing power.
It surely would be a nice addition to systems that exist in maps. But balance wise it might be hard.
What specificly should be important is the accessability of E. Initialy i would make it only easily reachable through C and D. A and B have it fully locked off. Since they have to defend 3 points having E instanlty easier to reach might be a bad idea. This at least would slow the progress of reaching it. Giving red to defend 2 points is in many cases already hard enough as gravelpit often shows. Especialy since those points are far away from each other (where in steel C, D and E are close to each other).
Once A or B is captured they open another path to C and D making it alot more reachable. In turn making E also easier to reach. However, E remains hard on this point. And red stays in the forward station (so they are between the 2 points that are open)
Then once 2 points are capped red moves to the 2nd spawn. And during that the other side point also gets easier to reach.
For C and D the results would be opening a major direct path to E from A or B. The result on this would be that instead of 3 points of which 2 can be taken a bit easier they now would have just 2 points to defend. The harder to reach one is countered as it became easier to reach.
And when both are capped the same happens for the other side. Blue gets 2 major paths to the point (note that gravelpit does this aswel although each path is split into 2, but you already have that by the older side paths).
Most important remains that EVERY capture should have something that matters. A minor buff from A yet a major buff from B and C could mean that they never will attempt to attack A unless it is to extend the timer.