FWIW--
the CG setups will change how the CAPS and any other bird handles
But -- the stock CAP 232 setup - will do absolutely flawless four points extended slow rolls -etc.. setup correctly with very little mix
The reasons why a lowered stab helps have been listed many times -by others also. frankly I can't buy into it .
Having built many CAPS with large/small / high/ low stabs - there is some difference but other than structural - none I would bother with.
making the stab larger makes for far greater differences in how the model performs
check out your own setup -- likely the horizontal tail has been fudged a fair bit .
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