autocomplete too smart

I type in the name of a variable (f.e.) and the autocompletion selection box appears so I can choose the option I wish. Fair enough so far. I escape out of that because I don't want to select anything (the variable name is already complete). However, when I tab, the autocomplete changes my variable to something it thinks is appropriate (usually an html tag). Having dismised the autocomplete selection, I would like to be able to tab freely, especially as I'm not writing cobol code and tabs are not significant.