Can you safely port the intake and exhaust ports of a S52 to flow as well as an S54's?

I know RMS had bad experiences with removing a lot of material from the exhaust side even with excellent gains.

They had few heads crack on them from the port job so if this were the case, would coating the inner walls of the exhaust port help keep the head from cracking assuming that heat and thinner exhaust walls is what made them crack.

Please do not mention valves or angle valve job or cams etc, just ports, thx.