Thank you everyone, for your inspiring ideas. There's a lot here that I now need to follow up.
I suppose if people didn't have many alternatives, then walking was considered the normal and simplest way of travelling.
I also like the idea that he may have crossed England in the north, to an east coast port, then travelled south - maybe to Lowestoft or Ipswich - by ship.
Robert's will states that some of his land in Rishangles is copyhold, and some freehold. Now, this in itself is highly complicated as my basic research has shown that there are two types of copyhold. At the time of writing his will, Robert mentions a tenant William Chittock. So that's something else to follow up.
Robert's may well have already owned this land, and he was sent south to manage it. Or perhaps it belonged to the Pulham family.
I have found previous postings on Rootschat about the Pulham family of Stradbroke, so will follow these up, too.
Whatever Robert's reasons for travelling the 200 miles he must have had a good reason - and known where he was going. Communication over such a distance must have been quite slow, and must have been done by messengers or personal visits (more expense).
Thanks again everyone - I will be off line now for a few days, but will check this post again as soon as I can.
Sue