Years and minutes are different scales of the same things. A year can be converted into minutes to determine the appropriateness of the relationship.
And while the 5% and 10% were not an accurate measure, the point that was trying to be made was valid.
A person that saves 30 minutes a day (interesting that that write took the end of the scale most beneficial to their arguement) = 48 days to gain 1 day of time (24 hours to day / .5 hours = 48). So, in a year (365 days) we gain 7.6 days per year. Average lifespan of say 76 years and we get 76*7.6= 577.6 days. Accounting for sleep @ 8 hours/day (count extra time showering, using toilet, etc. and let me average to this - don't argue you only sleep 6 hours a day) and you get 577.6*0.66=381.2 days.
So, effectively, your speeding gains you slightly over 1 year of life. Subtract from that the loss of time for being in accident, hospital costs, legal costs, court time, etc. from effects of speeding, as well as effects on blood pressure, etc. from speeding and I would side with the initial writer.
Slow down, take a couple of minutes all will be ok. Put on a podcast of the news or a digital reading of a book or something and make back that time you would otherwise lose.
The end result/argument is the same - don't speed!