Our elementary has some noticeable (to me) 2Es who don't "test" gifted/disabled, they test average, so they go along frustrated and unserved.

In most places there aren't enough 2Es to cluster them. There are a few places I've heard of... not here.

The best we have found is to put really good accommodations in place for both Es, including the gifted placement appropriate to the child's current needs, and adjust as we go.