The S&D may handle oil a little bit beter at the same grit than the TS&A, however, the TS&A is a VERY strong ball. By polishing the TS&A you're obviously limiting its oil handleing capabilities, so you could conceivably get another and leave it dusty. With the Awesome Hook that is coming out shortly you can seemingly get a similar reaction to the TS&A, but with a stronger move downlane. If you like the reaction that the TS&A is giving your wife you can drill it the same (as they both have strong asymetric cores) and either leave it in box finish, 500 grit or take it up to a higher grit sand. Any of these options are good.
Since the TS&A is so strong and for pretty much anyone would suffice as a heavy oil ball, i figure that your surface change is the main reason that it can't handle that heavy. This being said another option is to dull the TS&A and get a ball for lighter, something like the Awesome Flip could work for this purpose.
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four fried chickens and a coke[/size=4]
How can you have any pudding if you've dirtied your feet?