We routinely print ProE drawings to PDF, and we do it two different ways:
1) Using ProductView's batch publisher. This creates a .plt file from any files that change overnight in our Intralink database. The .plt file is then run through an application called ViewCompanion, which converts it to PDF (again in batch mode; you can buy this for about $30). By the way, the text is not text in the plot file either, evidenced to my when I was able to print Times New Roman Bold to a pen plotter! What a racket, but it colored in the text. Real text would either have returned an error or just printed the text in a default font, but there is no way a 15 year old HP Draftmaster II could have ever understood a True Type font. Ergo, it was NOT a font.
2) On the fly, using Adobe Acrobat's PDF Writer printer driver (available in all Standard installations of Acrobat--not Reader, mind you. BTW, this is NOT installed by default). We have a PDF .pcf file set up in Pro, and then we use the Windows Printer Manager and specify the PDF Writer (not Distiller). A tip: be certain to set the printer resolution to 600 dpi instead of 'SCREEN'; this eliminates 'spiky' text. The documents we print this way are exclusively text drawings from Pro/REPORT (manufacturing info sheets).
In neither of the above cases is ProE's 'text' really text in any sense of the word. You can't search it, you can't select it as text, and you certainly can't use Adobe's 'Touch Up Text' functions on it. And just looking at the screen and how the text is rasterize makes it appear as if you will not be able to make it text ever. At least not until PTC decides to change the underlying engine.
I did try once this crazy workaround, and it did work. Print the drawing to a tiff file and then use OmniPage Pro to read it in and run OCR on it. It worked, but was more effort than it was worth.
Regards Pete