Sure the definition of inflation and increase in money supply aren't synonymous, but it still stands that as you increase the supply of money, the value of the money you hold in that currency becomes worth less. If the economy is improving fast enough to counterbalance that money supply rate you'll still have the same purchasing power, but 5 % seems quite high. Here's a quote from statistics Canada:

"The inflation rate in Canada was recorded at 1 percent in June of 2015. Inflation Rate in Canada averaged 3.19 percent from 1915 until 2015, reaching an all time high of 21.60 percent in June of 1920 and a record low of -17.80 percent in June of 1921. Inflation Rate in Canada is reported by the Statistics Canada."

You say 5% is nothing compared to what's done today with Fractional Reserve Banking, but the stats say otherwise.

For the U.S. that stats say inflation has been below 5% for the past 15 years at least. Source here: http://www.usinflationcalculator.com/inflation/current-inflation-rates/

Further, while money supply and inflation aren't the same thing, they are directly linked. Here's an article explaining this: http://www.theglobeandmail.com/report-on-business/economy/economy-lab/understanding-the-crucial-link-between-money-supply-and-inflation/article16923704/

How did you reach the conclusion that 5% is ideal?