Hi Brian,
Yes! I agree. Every time we do a release, "a few" features we had hoped to be able to implement need to be pushed to the next release, and it seems that support for colspan is one that is repeatedly pushed. Until a customer sponsors the feature (in which case we "have" to do it!), all I can say is that we'll try our best, but can't make any guarantee. Hopefully 2017.2 will be the one :).
Alex
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