Definition of \"Mechanism\" needs clarification

Name: Jan Richards (on behalf of UAWG)
Email: jan.richards@utoronto.ca
Affiliation: WAI-UAWG
Document: W2
Item Number: Appendix A: Glossary
Part of Item: 
Comment Type: technical
Summary of Issue: Definition of \"Mechanism\" needs clarification
Comment (Including rationale for any proposed change):
The definition of \"Mechanism\" mentions user agents but without a link.

Proposed Change:
Links to \"user agent\" and perhaps a connection with \"Accessibility Supported\".