This is the first of a two-part column. The second part will appear on Wednesday.Relying on the “mend the hold” doctrine — as broadly articulated by the Illinois Supreme Court in 1912 — Izumi Saika and Mohammad Shakibai argued that Ocwen Loan Servicing should be barred from asserting a defense it did not mention before they sued the company for allegedly breaching a loan modification agreement.Before Saika and Shakibai sued, Ocwen reportedly claimed they did not qualify for a modification of their …