I've never been sure what the problem with 'overusing' the word 'that' is. It seems to me [that] someone made the rule one day and everyone else followed it. The online source I was reading equates overusing 'that' with overusing 'like' in sentences in her earlier years. As far as I can tell, unlike the nonsensical 'like,' there are very few instances where the word 'that' has no grammatical function in a sentence.
In my opinion, using too few of the word is a worse problem than using too many of them. I would appreciate other opinions on this because I'm reviewing this manuscript where the writer is closely following this 'that-bursting' rule and it is frustrating because it is yielding sentences like:
John told him on their way to the park [that] James would be waiting there.
The greater tragedy was [that] the rescuers would later return without the girl.
Sometimes it even occasions too many commas (I guess because instinctively the writer knows there is something missing but they are afraid to admit it is the word they have kept out):
Having agreed with Peter[,] he would be in the office early the next day, he went on home to bed.
As opposed to:
Having agreed with Peter [that] he would be in the office early the next day, he went on home to bed.
Without doubt, no word or phrase should be overused in writing and writers should try to strike a good balance to where no word or phrase is sticking out in particular. But no word should be vilified if it is grammatically correct to use it.
Am I just being irreverent of the rule against 'that'?