Note my emphasis added above.
It doesn't strain credibility that Apple would be evaluating more than one design.
...and some of the rumours have also been saying that the larger phone has been 'delayed'.
Although its not impossible I'd be surprised if Apple actually introduced a huge iPhone and a slightly huge-er one unless there was some other distinction between them.
You really don't have the bold rumors I stated rumors because people are complaining about the rumors. If the rumors are true then their complaints are valid, and there is nothing wrong with complaining about rumors, if Apple is still deciding on one of the two models they are working on the complaints could make them lean toward the other.