Advantages and disadvantages of english system

Explain the English System of judicial precedent its advantages and disadvantages and discuss whether any alternative systems exist?

Lorenzo works as a salesman in the Delmas Computers Inc store. His contract of employment provides for an annual salary of £18,000 and commission payments (at 9 per cent) on any computers and peripherals he sells. In the previous 3 years, the commission payments have amounted to an average of £12,500.

The world economic downturn adversely affected the store. The manager, Francesco, informed Lorenzo that the business was in severe financial trouble and that he must reduce the firm’s outgoings. In response, Francesco asked Lorenzo if he would forgo his salary for 2016, 2017 and 2018, and accept payments of commission only. Francesco explained to Lorenzo that this was required of him and all other staff or the business would probably not survive and it would have to be wound up owing substantial debts to creditors. As such, Lorenzo accepted the variation of the contract.

In 2018 the economy began to grow, and in small part due to governmental incentives for investment in information technology, the store managed to trade its way through the difficult times and in making a healthy profit. As such, Lorenzo feels that he should be able to receive his wages for 2018 and not simply have to rely on his commission as agreed in 2016. He also wishes to know if he can successfully claim for his wages from 2016 and 2017 as Delmas Computers Inc has sufficient profits to repay this money.

Advise Lorenzo whether he can obtain his wages for 2018, and also whether he would have any claim for his wages he agreed not to accept in the years 2016 and 2017. (You must restrict your answers to contractual issues rather than any employment obligations that may be present)