Your assumption is correct Lawrence!
I will reveal that I had searched out the salad leaves called Rocket, with no success in finding leaves like this but now I have found one which is close. I have grown Rocket, once only, the flavour wasn't anything to write home about. It was bland and a little bitter, but I'm sure some Rocket has flavour worth making the effort.
The growth habit could well fit, read what it says here:
The more rocket you pick the more will grow. Either cut a few leaves at a time or slice off the whole plant just above the surface of the soil and wait for the stump to re-sprout.
http://www.paddocks-allotments...
The bolded bit may explain the root stump with several growths. The jury is still out though! The leaves of Rocket are often lobed but there's much research and development going on so who knows what selections have been made.
Enlarge the photo on the next link and you can see some leaves which are not lobed.
https://aristonorganic.wordpre...
