Distributed MoreLikeThis has problems when q.op=AND

Distributed MoreLikeThis seems to result in "regular" distributed queries using the termvectors found in the example document.

If q.op=AND in the initial request, then the distributed queries with the termvectors will ALSO have q.op=AND, which for my tests, has resulted in no matches. If I send the MLT request to a handler using edismax, or include q.op=OR, then it works as expected. It's very slow, which I'll bring up in another issue.

Should it remove that parameter or assign it to OR? Should it ultimately pay attention to the mlt.operator mentioned in SOLR-5160, which is not implemented at this time?