I think it's troublesome. Living in Canada at least 2 years in 5 years is applied for any time period after you landed. Every time when you re-enter Canada, Immigration Canada will check if you have lived in Canada for 2 years in last 5 years, if yes, no problem for you. If no, Immigration Canada will see if you have enough time to live in Canada in future to meet the 2 years/5years requirement. For example, if you have left Canada for more than 3 years without any special permit to waive the 2/5 years requirement, which means even you will live all the time in future, you can not meet 2/5 years requirement for the period since you left Canada last time. You will be denied to enter Canada.
But there are some ways to waive the 2/5 years requirement, such as work for Canadian company oversea, special permit etc. Your friend had better inquiry the Canadian embassy or immigration lawyers as soon as possible.
Good luck.