TensorRT 2 EA and concat layers

I am confused, the TensorRT2 user guide states that the build phase performs:

“elision of concatenation layers by directing layer outputs to the correct eventual destination”

Doesn’t this mean that the outputs are copied appropriately into memory, rather than explicitly executing concat code. This still effectively implementing concat layer, right?

Anyways, I get a failed assertion during the build phase when analyzing the first concat layer

main: cudnnBuilder2.cpp:371: void nvinfer1::builder::checkSanity(const nvinfer1::builder::Graph&): Assertion `readRegions.find(t->region.get()) == readRegions.end()' failed.

Any workarounds, other than splitting up the pipeline with custom concat layer?