How I actually play it
Book the decision, not the calendar.
01
Decide on the holding first. Still want it? Keep it. If not, the tax saving is a bonus, not the reason to sell.
02
Match the token to the bill. A short term loss is the flexible one. Spend it on a short term gain first, where the rate is highest.
03
Do it before the year closes, and file on time. The netting is annual. The 8 year carry forward needs a filed return.
The market decides whether a position goes red. You decide whether that red is dead weight or a coupon you cash.