I have surpassed the hard coded brick limit. All that happens is you do not ghost new bricks being planted. The are basically invisible. You can still collide with them. For every brick that is killed after surpassing the limit, a nearby brick will ghost. It does not matter how many bricks you can see currently the effect is the same (unless you happen to have not been near enough bricks not to ghost the number required to surpass the limit). The odd thing is if you rejoin a server that surpasses the limit the bricks that ghost may not be the same bricks you ghosted previously. This can lead to some odd situations.