Is this sentence correct or not? -------- It’s thought that there is as much as 10 times the amount of gas in methane hydrates than in shale for instance. ------------ This sentence is from a BBC story on its website. Somebody thought it is incorrect and rewrote it as: ----- It’s thought that there is as much as 10 times the amount of <MORE> gas in methane hydrates than in shale for instance. ---- But I think the revised version is still incorrect and a possible corrected version is: ---- It’s thought that there is as much <GAS> in methane hydrate as 10 times the amount ( of < THAT>) in shale, for instance. But then again, somebody else has come to the original's defence, saying it's correct and perfect. So, dear native Egnlish speakers, what do you think about all these sentences?