Proficiencies and Skill Levels

[Foxiekins]

Page 56 of 6th Edition, Volume 1, states that Skill Levels may not be applied to the 8- chance resulting from a Familiarity.  But it doesn't explicitly state that this restriction applies to a 10- Proficiency.  In another thread, someone suggested them as a less expensive version that a series of overall skill levels could benefit.  Is this allowed, or does the restriction apply to Proficiency as well...?

[Derek Hiemforth]

Also on 6E1 p56, in the last sentence under Familiarity and Proficiency, it says, "Proficiency functions just like Familiarity...."  This means that Proficiencies are subject to the same restriction about Skill Levels not applying.