I have watched the teller sit and enter the checks to be cleared while at my bank. I can say with absolute certainty they did not take enough time to have read the written (alphabetic) amount.
Tellers are trained to quickly review various parts of a check for error, including names, dates, and signatures, but also the amounts. That being said, tellers receive hundreds of checks a day, and while a few will slip by with mistakes, you'd be surprised at how many errors a teller can catch. Catching bad checks is part of their job. You can try slipping a teller a check with an error, and maybe it will get past him, but I definitely wouldn't guarantee it. I used to catch checks with mistakes in the amount all the time. Our bank's policy was to use the amount that was alphabetically spelled. As someone above already pointed out, their bank's policy was to use the numerical amount.
It sounds like the check will get deposited, but the amount that gets entered will probably depend on the bank's policies and whether or not the teller catches the mistake.