Related Clues:

• Persistent smell returns, say, catching current
• Pig-headed botanist takes last of rose
• Pig-headed old boy at home in Texas perhaps
• Hard-hearted alumnus expected to harbour traitor
• Implacable Bond, with one outer failing on the surface
• Tenaciously unwilling to yield
• Firm over bishop with position to secure in ...
• ... this, a doubter in a frenzy
• Fix it on beast like a mule
• Refusing to bend, old boy, say, has to be carried around home
• Convert a doubter not easily swayed
• Pig-headed and old, at best in being treated
• Stubborn stain needs to be shifted
• Make a speech about British — some of the French hard to persuade
• Old boy in state that's unstable and unlikely to change