This has happened to me, I usually go out to the middle of the lane and it still happens. If you are keeping the lane down, anyone jumping in after you hit it just zip right by like its nothing. Definitely should be fixed somehow. Other than that you pretty much have to sit and keep your eye on the chat, see who's in neighboring systems and as soon as you see they jumped in, hit it. But that doesn't leave you very much time.
And yeah not liking the idea of people exploiting this to get their ships past pirates at a gate. This is not the matrix.