Possible Clues:

• Some how-to book targets?
• 'Silly me, I had tttttttttt, it seems (6)'
• Perhaps I'd have T x X to make them so silly
• 'Stupidly, I had T x 10, seemingly for them (6)'
• Dimwits
• I do sit with the silly ones
• I had tents, perhaps, for fools
• 11 + ¿.. - so silly!
• I had T x X perhaps - silly!
• Dim bulbs