The wires make it easier. Here's what most people do: With green stretchy tape, tie the cordons to a stick of bamboo to keep the cordon straight. With anything else, tie the bamboo to the wires. The key is the bamboo and the green stretchy tape, which, in combination, will keep your cordons straight and parallel to one another. Otherwise, your cordons will most likely curve up and toward the sun.

What you've done is somewhat different than is commonly done, but perfectly OK.

Here's what is commonly done: Vertical posts on either end serve as "bookends" with horizonatal wires stretched in between the end posts. In this scenario, the wires provide support to the bamboo sticks (which are attached to each cordon with green strechy tape that does not bind into the trees). It's usually cheaper to do it with vertical end posts and horizontal wires than with individual stakes.

Another advantage of the "end-posts-with-wires" scenario: The wires also allow you to train all your cordons to grow at the same rate of speed. Here's how this is accomplished: (1.) tilt upward one of more of the cordons to a steeper angle (which encourages growth of the cordon) OR (2.) tilt downward one or more of the cordons to a flatter angle (which discourages growth of the cordon). Tilting one or more upwards or downwards encourages your cordons to grow "in sync" with one another in case they might be growing at different speeds.

But what you've described is OK too. Whether you train your cordons with individual stakes (as you are apparently doing) or in the manner I've described, here's an important TIP: Do NOT bind your condons 100% of the way up from the bottom to the very tops with green stretchy tape. Instead, in the training stages, leave the topmost 8" to 12" or so loose, which will cause each tip to curve upward and grow more quickly than if you had bound it all the way up. This will encourage each cordon to grow faster to the height you want it to reach.

Yes, synchronizing the growth of your cordons is mostly an aesthetic consideration. In order to encourage fruit production, you will need to learn how to "summer prune" (also called the "modified Lorette system"). Basically, your focus will be on learning (a.) how and why to prune off the terminal bud of each cordon (to encourage side branching), as well as (b.) how, why, and when to summer prune the laterals coming off the side branches [which, in combination with (a.) above, will encourage the production of fruit spurs -- which encourages the growth of more fruit].