1) For retirement plans, it has no effect whatsoever Utterly wrong. 2) For regular accounts, it only has a bearing on what you do if you do it within the last 30 days of the year, or if you do not liquidate your position during that year... Not even wrong.
BTW I was tickled by the BV thread about your options trading. Both you and everyone else involved were apparently unaware that in every options venue on this continent execution priority is dictated by order size than than time of receipt.