So that answers my question a few days ago that 3 consecutive on arrival visas of 60 days where you hit the 180 day limit, appears to be what you can get away with. But as stated by several members earlier this can be at the discretion of the particular IO (Immigration Officer). However my guess would be that if you are well dressed and groomed, and don't look like some of the reprobates I saw on the Ranong/Victoria Point (Myanmar) border runs, I did several years ago now, then you will not necessarily attract too much attention from any one particular Thai IO.
Yes it is probably too early in this new immigration 60 visa on arrival to get someone who has tested the new system limit sufficiently. I would most likely only do it once or twice....but who knows. I would guess that sooner or later someone will abuse this 60 day recurring, via border runs, to the extent that they crackdown on it. I think the old 15 day land border run visas were done to try and get rid of lol perceived undesirables that were existing in Thailand 'on the smell of an oily rag' . But who knows, another military coup, could turn everything upside down again. That is the one that Thailand is good at ..... military coups, the 2006 coup that toppled Taksin Shinawatra , was very benign.