comparative of the adjective "grave"

Question

I had written

The effect of traumatic experience may be graver if...

and the editor has corrected it to

The effect of traumatic experience may be more grave if...

Surely grave conforms to the regular rules for comparatives? Am I missing something? (I note that graver is also a tool for making engravings - but that's irrelevant.)

Answer 1

The Oxford Learner's Dictionaries gives "grave, graver, gravest". Collins also gives "comparative graver, superlative gravest." If the topic was bereavement, perhaps the editor would avoid that word altogether and use "more serious".

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