刚看到Reading14,等我看到再回答你好了

My understanding is that issuer of a credit bond wants to seek
protection,and increases in credit bond supply indicates the demand for
protection increases, therefore spread may not tighten.

[此贴子已经被作者于2009-5-3 5:48:00编辑过]

if you read carefully for the first paragraph under "Primary market Analysis" on p.67 of reading 30, you can notice that "supply will hurt spreads"  may be true for single issuer but not generally true for entire credit market which depends on many other factors. Even if it is true for investment-grade credit market, as you quoted in the second paragraph, Warren's trading universe may include bonds below investment grades, as shown in statements regarding Select high-performance fund, which includes B grade bonds.

I have to agree with you that that materials on the section is not very clear.