That is good advice! Sometimes the teachers get so fixated on a particular form for something (in this case, a thesis statement), though, that they suck the life out of academic writing.
The context of the thesis statement is important, too! It seems goofy to require the kids to make the thesis all one long sentence.
It will even help to do it like this:
...these women were met with a whirlwind of conflicting attitudes: the attitudes from enlightened intellectuals were positive, as were the attitudes from fellow women scientists -- but, attitudes from non-enlightened scientists and traditional women were negative and filled with discontent."
Kevin, EssayForum.com