Whenever a miner succeeds in mining, will the reward of the mining pool be provided to the miner immediately? To some extent, will this not cause block congestion? 
A miner succeeds in mining faster than a pool can send, if you are using a PPS pool, every share you submit adds a tiny profit to your balance, the fees to send that is larger by a few orders of magnitude, this will not only cause " block congestion" it will probably cause the pool server to hang:-\, imagine having to send the rewards of a few thousands miners every second or so, it makes no sense what so ever.
Most pools have a daily payout at a specified time like 4 AM GMT, anyone who has a balance above the minimum threshold will receive their earnings, most PPS pools will not send you the freshly mined bitcoin, i.e, you don't need to wait for 101 blocks to send it, they use inputs from prior blocks which you can spend right after 1 block confirmation on most wallets.
