I would agree with Jeff's comment about detailing the window prior to squeegeeing off!
Though it is a little different to detailing
after you have squeegee'd.
But unless the glass is really dirty, try not to use the applicator close to the edges of the window pane, in particular the top edge.
Sometimes it can be the weather conditions or the type of beading that holds the window pane in that can also cause 'bleeding' to occur.
Make sure your rubbers are cut cleanly, and are protruding only a couple of mm or an eigth of an inch or so from the ends of the channel.
Also check the rubber when you are getting the faint line being left behind, on a fresh rubber, you can quickly get a little 'nib' of rubber form through wear right at the end corner of the squeegee rubber.
I usually just pinch it off with my fingernail.
Dog ear your squeegee channel (if you don't already that is) This has been a great tip that has been enthused over on both this forum and over on another forum.
In fact there is a really good description plus pics on how to do it.
Hang on, I'll just nip over there and see if I can find the post so I can pop in a link......others have done this intricately trciky manouvre.....can't be that hard...can it???
http://www.another forum.co.uk/?board=win_clng_issues;action=display;num=1081405008;start=3#3
Nope, not that hard at all
Just use a pliars to bend your channel as the pics show.
Another possible cause of that faint edge can be having whatever solution you use in water at too strong a dilution rate.
If you are using washing up liquid, try to use as little as possible, if you dip your fingers into the water and it feels slippery between your fingers then it is way too strong
If you don't already use the specialist liquids, GG3/4, Unger liquid and so on, give them a try.
If you are not already a user of them though, be warned! they can take some getting used too
Ian