'doubt that' idiom

[vscidd]

OG says that 'doubt that' should be used in negative contexts such as 'there is no doubt that he will come', and 'doubt whether' should be used in positive contexts such as' I doubt whether he will come.
MGMAT SC guide mentions only 'doubt that' in their list of idioms. Is 'doubt whether' not the proper use according to MGMAT?

[s.aamershah]

4th Edition MGMAT SC strategy guide, Chapter 9 pg. 153
references "DOUBT" in the idiom list.

The SC guide states "The GMAT claims that DOUBT, used in a positive statement without NOT or NO, should be followed by WHEATHER or IF, not THAT.) Take a look at the examples and I think that answers your question.

[esledge]

Thanks, s.aamershah, for answering!

In general, vscidd, MGMAT agrees with what the OG says, even when we don't ;-) They make the rules, and we follow them.