Oh yes, it certainly has. I've been playing with more cartoon and caricature methods of late, as well as doing some commisions, and I'm now in the process of updating my methods (again).
As described in previous posts, I usually colour my line work by underpainting in water colours, and then detailing with colour pencils. I recently bought Jeff Miracola's acrylic painting DVD, and it made me rethink my current process. Firstly, I've been using pigment markers or brushes to do my linework, but I've always been happier using my Zebra brush pen - but it's not waterproof. After watching Jeff's videos on youtube, I thought I'd try using a fixing spray to seal the paper after I did my linework - and waddya know, it works! I can use my Zebra brush pen, with all its abilities, and still colour the work with no ink bleeding - marvelous!
I then tried to do the underpainting using acrylic inks (FW Ink) which worked, and here's the result...
As an aside, my next piece will be on illustration / watercolour board. I'm tempted to prime the board with Gesso (another little trick from Jeff) before I start, to make sure the board is properly sealed first, but as I have 3 boards, I might just have a go with just the fixing spray first.