Well yeah, the rules would have to be a bit more complex than that, but do you not like the general idea?
Because I think a whole load of really obvious rubbish gets patented at the moment, but I do think the foundations of the patent system and the utility of patents ought to be salvaged.
You wouldn't know what your competitors are filing within months of it happening and then have any opportunity to do anything about it.
Applications are only published to the public either 18 months after the earliest priority date or after the patent has been granted.
The only other time you might know what they were up to is if they made a public disclosure about the technology. But as that has implications for their own filing strategy, they're not likely to do that in a way that left you an opportunity.