no. the law requires proration see IRS PUB 936
so if you had two $750K mortgages for a full year about 50% of the interest on each would be deductible.
in fact, it's the average balances that are used. so if one had an average balance of $740 and the Other had an average balance of $700 and you paid $90K in interest on both mortgages your mortgage interest deduction would be
$750K (max) divided by average balance of $1440 times $90K = about $47K
