Suz, many thanks also.

I acknowledge that this has been familiar and, perhaps, wearisome territory for you: another newbie to the forum, keen to give solidity to old family stories. However, I reiterate that there is a
prima facie case for John Bowman having GRT roots, not a powerful one, but one that is nonetheless worthwhile investigating (on the basis of the name and occupation having GRT associations). I write this because I couldn't see how points you made against the hypothesis actually served as evidence against it, and thus left me feeling slightly confused.
To wit:
- "a residence not a tent or caravan (as is usual in travellers)". By integrating into the sedantry community it would be expected that tents and caravans have been eschewed in favour of bricks and mortar.
- in relation to the point about the John Bowman of Appleby. As alluded to, I very quickly realised he wasn't my man when I saw him on the 1851 census. But, for that matter, neither the point that he worked on a farm or became a woodsman would not be sufficient to exclude
that John Bowman as a GRT candidate. Farms were, and remain, prime venues for employment. [I recall that Ewan MacColl song: 'The farmer said the work's all done/it's time that you were moving on'. I digress!] And surely, his learning how to handle an axe would not have been beyond his skill-capacity had he become settled.
- My describing Clark's Yard as more of a "ramshackle slum" was not an exercise in wishful thinking done to make John Bowman to appear more likely of GRT stock. I would submit that it shares many of the characteristics of a slum: cramped, irregular, decrepit housing, set back from a main thoroughfare by a long narrow passage, nested in darkness amongst a hodgepodge of other buildings - inns, stables, warehouses, workshops - and inhabited by poor people. The yard received sewering and paving in 1857, but a newly-built mill worker's terrace in the town must have seemed palatial in comparison. The snapshot the 1861 census provides coincides with the onset of the Lancashire Cotton Famine, and descriptions of Church Street and its environs in 1865 are Dickensian in the sense of vice and destitution conveyed. I wager that if one had to choose a place to live in Preston in 1861 you would struggle to find many superior picture-postcard examples of its squalor. The yard had existed since at least the C17th and its remaining houses were demolished in the 1930s as they were deemed unfit for human habitation; this programme was known popularly as 'slum clearance'. Winckley Square, it was NOT! It was just the sort of place that one could reasonably imagine an itinerant gispy tinman taking up residence.
Finally, on this point, I would contend that it is not reasonable to deduce that the area was "not really" slumlike on the basis that it counted amongst its residents a "shopman a boot & shoe maker people in various types of employment in the cotton industry". If we look at that archetypal mother-of-all-slums, Old Nichol's Rookery in Bethnal Green, on the census of the same year, we find - in addition to shopmen, and boot and shoemakers - cabinet makers, marble masons, carpet weavers, looking glass makers, french polishers, blacksmiths, glass blowers, tinplate workers, engineers, and silk-weavers. This was indeed the sort of place that members of the GRT community and their descendants settled, and, again, it is well to note, all of them are in a residence, not a tent or caravan.
In summary, Suz, I do not doubt that for, say, every ten family stories of "gypsy blood" nine are without apparent foundation, but we should be careful not to prematurely exclude those that are out of habit and without good evidence and reasoning; to do so is to invert the sort of confirmation bias I myself have tried to be wary of in chasing the ghost of John Bowman.
