What's this ugly stuff on my roots?

[crhabq]

Today I was looking a my quince when I noticed that may of the leaves looked dry and crispy and shoot ends were wilting. I looked at the soil and thought it was too dry so I went and immersed the pond pot in my water barrel. I sat the pot down to trim off the dry shoots and crispy leaves. Worms started coming out of the pot. Now this was my beginner soil mix from last year which was vermiculite, and garden center potting soil. Until now I didn't worry about this because the quince seemed quite happy in it and grew vigorously this year.
Now I felt as if I was damned if I do and damned if I don't so I went ahead and repotted it into a better (i.e., faster draining) soil mix.
While combing out the roots, I kept finding a gray, firm aspic-like body on the roots. I had found the same thing on a hinoki cypress I repotted last year. It does not look like an images of mycorrhizal fungus that I can find on google images. Its so ugly and slug body-like that I can't believe that it does my plants any good.
Any ideas of what this is?

 

[Vance Wood]

Does it smell sweet like fresh vegetables or more like sewarage?

 

[crhabq]

I didn't notice any particular smell to it. It did not smell bad, but then again I smoke alot and my sense of smell is not particularly keen. But no, there was no sewage smell.