(mounts soapbox)
The OP's misconception is a logical outcome of the lousy fact that the "AMT" line on 1040 the difference of the Tentative Minimum Tax and the (for lack of a better term) Regular Tax: AMT = TMT - RT
There are multiple ways to shrink a difference (and so make the AMT line smaller), but only a couple of them will reduce the bottom line tax you pay and some will make you pay more!
- Increase both TMT and RT but increase RT more. This will reduce AMT but will result in you paying MORE tax.
- Leave TMT alone but increase RT. This will reduce AMT but will leave the tax out pay unchanged. (If it were allowed, this is the category the OP's idea falls into, so as someone already said, it would accomplish nothing even if allowed).
- Leave RT alone but decrease TMT. This will reduce what you actually pay.
- Reduce both TMT and RT but reduce TMT more. This will reduce what you actually pay.
I note that in theory you could reduce both TMT and RT but reduce *RT* more. This will actually increase the "AMT" line on your 1040 but will nevertheless leave you paying less tax.
I know it'll never happen but I wish the AMT was implemented as a fully parallel set of forms 1040-AMT, Sched A-AMT, etc. for those forms where there are different AMT and regular tax rules instead of the current system of reconciling all differences on 6251 and reporting the different between TMT and RT as "AMT" on 1040.
Then it would be much more clear exactly what is going on with AMT and what strategies would actually reduce your bottom-line tax.
-- Rich Carreiro snipped-for-privacy@rlcarr.com