You are trying to solve the wrong problem. What you need to do is run repair and optimize against this table frequently – for example, every half an hour. You can use the command line mysql client command and your host's CRON job system to automate that.
FWIW what you had in mind had a few holes in its planning. Let's say that you are making a copy of the table. Any new data inserted in the table would be lost as soon as you restore it. Moreover, you cannot make a copy of the table under a different name. Furthermore you cannot copy the table if it's already broken. So unless you were constantly taking a backup of the table (which is really bad for your server!) you couldn't guarantee a semi-consistent backup copy of that table. Then again, you'd need to write some software to detect when the table is broken, delete it and restore it from the backup. Suddenly this sounds like a Rube Goldberg contraption instead of a solution to the simple problem of MyISAM tables becoming corrupt on frequent access. Think simple.
Nicholas K. Dionysopoulos
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