Unfortunatelly, I need to go afk for a while. Here is a spoiler,
DO NOT HOVER THE NEXT LINK ->
.I hope to read better math when I'm back.
Matches with what I posted if one assumes a flat difficulty. Difficulty has been increasing in Feb thus confirmation times are getting faster. Look at the average confirmation time in Jan and compare that to the difficulty swings within that month and you will see what I mean.
https://blockchain.info/charts/avg-confirmation-time?timespan=60days&showDataPoints=false&daysAverageString=1&show_header=true&scale=0&address=https://bitcoinwisdom.com/bitcoin/difficultyAfter the retarget on jan 12th increasing difficulty by 8.2% you can see the very next day confirmation time averages shoot up to 11 minutes because a ton of miners were pulled.
Confirmation time is 5 min in average. 10 minutes is the gap between blocks.
This is false. One should assume most confirmations to take ~7-8 minutes on average because of the Poisson distribution and difficulty increasing as a normal trend. I see that you seem to be suggesting that one should expect a confirmation in 5 minutes because of the tx happening at an arbitrary time during the blocks being processed but this only applies to the first confirmation and even so the correct response should have been that one should expect:
1) an average of half of the of the first confirmations to occur in ~3.5-4minutes
2) Subsequent confirmations on a Tx to occur with a probability of half being confirmed in ~6 to 7 minutes, with an total average of ~7.5 min