confirmation and number of transaction/sec (TPS) are the same thing and it is 7 TPS for bitcoin i was right. and as i said the restriction factor is the size of the block that coin has and the time between the blocks and also i suppose the average size of the transactions.
in the end it doesn't matter BTC, DASH or ... if you can only put ~4000 transactions in one block they will all have the same restriction.
solution bigger block, shorter time between blocks, smaller transactions.
each of these have their own problems though which i am not expert enough to discuss at length but in short for example a bigger block or blocks that are mined with 2 minutes interval means size of the blockchain will be 100 GB in 500 days (it took bitcoin 7 years to reach 100 GB)
edit
ZEIT & Mint both have 20X BTC current transactions capacity.
Both running at a 30 second block speed.
here is an example for you. 30 seconds and if i take his word for it 20X current capacity means blockchain size is also growing 20x faster.
bitcoin : 7 years : 100 GB
ZEIT : ~100 days : 100 GB
(assuming it handles the same amount of transaction bitcoin is handling) having the potential is useless as long as it is not used.
also another problem that i forgot to mention is
orphan blocks which will increase drastically with shorter time interval blocks.
