How to avoid interleaved output with ecco=t?

[laurapspector]

I am doing overlap-based error correction with bbmerge and I want only the error-corrected Read 1 reads. I have set ecco=t, mix=f, merge=f because I want to keep reads that are mergeable (have extensive overlap), but I don't want to merge them. If I provide only one output file ('out'), I get an interleaved file. If I also provide 'out2' to try to separate Read 1 and Read 2, the output files aren't even created (neither read files nor histogram) even though the insert size/stats are all reported. Removing 'merge=f' doesn't affect the outcome. How can I get the mergeable (but not merged), error-corrected Read 1 reads in a non-interleaved file?