Idea for promos + [poll]

When you are at 95 - 99 lp or smthing and enter promos after you win while you were at 99 lp, you will gain some lp(let's say 75%) when you will succesfully complete the promos. For example you are at 99 lp. Win a game, then win the promos, and you will have 15 lp in your own division(15 when you usually gain 20, because 15 is 75% of 20). You gain a full percentage(100%) when you get a league up. Example from silver I to gold V. The percentage gain is lowered by 25% when you lose 1 (2 on league promos) games in promos. This also applies on getting a league up, however with 1 loss you gain 87.5% of the lp and 75% with 2 losses.