can someone explain "lane swap meta" in LCS games?

it's the lowest risk strategy possible with high rewards

you could lane vs an opponent and duke it out then have your jungler and mid come by to force down a tower once you get the upper hand or whittle it down etc etc

or you could just not lane at all and still get xp gold and tower

It's basically skipping laningfase avoiding all interaction so you can't possibly mess up in lane, the only thing which can happen is the other team is slightly faster thus eventually wins the game if both parties keep going like this

its broing af its basically both team's be like yo let's pve for 20 minutes then whoever is ahead will win a teamfight and end the game

As stated, it's mostly to avoid unfavorable bot lane matchups and it's also very tricky to pull off properly. If you and your team are confident with doing it (and following up) properly, then it's a huge payoff if they mess up. That goes for your team also. If you fail and they succeed, you just put them ahead. Ahead being more in terms of map pressure which eventually leads to gold and xp leads.

Top and Bot/Sup constantly switch lanes so that Top is always farming a wave, and Bot/Sup is always trying to siege a tower.

When the tower is under control, Top joins the Bot/Sup to claim tower gold and clean up the next wave or two. Bot/Sup switch lanes and push the next tower.

Rinse and repeat.

It initially existed to avoid bad lane matchups, you gave up dragon controll and set your and the opposing sololaner behind while giving free-fram to your adc and easy early roaming to the support. It was a kinda band aid for pick/bans gone wrong in terms of laneing matchups.

However with S6, the game overall is so snowbally that laneswas generally are a save call to avoid early snowballs, so any team that thinks it can outplay their opponents in the mid-lategame go for a laneswap so they don't risk getting snowballed upon, and they don't even pay for it as they can riftherald for dragon. it's susally the 'weaker' teams in lcs that try to get standart lanes and go for pocket picks, hopeing they can catch their opponents of guard and snowball the game early, because they know that they most likely will get outplayed later on.

Now with the recent changes, initiateing a laneswap(sending your duo top) will come at a sigificant cost, so if it is done at all, it will be done to avoid really bad lane matchups as the cost of doing it is to high to use it as a default or even opportunistic strat.

The reason they do it is that your team denies your top laner early farm/exp to do the same to the enemy team while also causing towers to be traded early causing a game with larger amounts of starting gold. Bascially if you want to avoid a situation your bot lane can die early in. Of course by doing this you do give up drag control.

Also it becomes very effective if the enemy team doesn't know how to do it as they wont pull down enough people to take the turret causing it to be a safe early game for both bot lanes and a hard early game for both top laners but giving extra gold to the team that initiated the swap because they got a turret and the enemy team didn't.

Adc ges top, top laner goes bot and thats it.