I will say, whenever you’re out to propose something, try to do some research and get their PoV and counter-argue accordingly.
Meaning, if the feature isn’t here, then there must be a reason for it. Check out what they said previously, if available. That way, you will have knowledge and facts.
Accordingly look for some effective arguments and measures. That way, the chances of your suggestion being taken multiply manifold. For example-
As people have said, that “it might be misused during ongoing contests.”
If you can come up with something like “But we can do so-so and this and…/ And by all this we can provide this feature without a compromise on contests.”
That way, there are high chances of your suggestion getting accepted
On Topic- For everyone who have answered, can someone counter-argue his point that “all major websites allow multiple sessions?”. We cannot neglect that point if its genuine. If other websites found a way to provide the feature without any compromise on contests, then why cant codechef? It’d be great if anyone can comment/counter-argue on that point :).