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[SkenfromLMF]

I would think there needs to be a freeze applied to a team that moved up to land a top 4 pick.
Depending on how far a team moved up it is frozen for a few years, and in the same way a team that lost draft position in a recent draft should have that move down offset part of a freeze.

Something along the lines of a 6 year window that teams moving up from 7 and greater to #1 are ineligible to MOVE UP to the top 4 again in the window;
Scale the window so it is 5 years for going to 2; 4 years for going to 3; 3 years for going to 4.
Teams moving up from 5th or 6th can receive a window that prevents moving up again in a much shorter period (1-3 years: up from 5 - 3, 2, 1, 1; up from 6 - 3, 2, 2, 1)

So in theory Dallas, if they do not make the playoffs, would not be eligible to move up in this draft.

You would NOT want a team to be penalized for having bad luck as Dallas was in the '90s. Dallas consecutively drafted 4, 4, and 2 and was moved down via the lottery all 3 years 92-94.

BTW this system does not preclude a bad team from being in the lottery consecutive years, it simply means they can only move down once they have won recently. Any team moving down 2 (or more) slots has a year removed from their current or next window.

I would also see this system of freezes becoming a possible penalty for teams obviously violating sprit of the game (tanking) guidelines. If there is suspected tanking resulting in a top 4 pick then extend the freeze window; it would have to be sure-fire violations to freeze before the lottery, but there was that Joe Smith in Minnesota incident, so don't say never