I don't think it's buying points that raises the issue. Most of the time, the decision involves choosing between different spreads/prices at different books.
For example, if I can get +7 -105 at 5Dimes, or +7.5 -111 at another book, which is better? That, to me, is where Ganchrow's calculator comes in handy.
From your own followup post, I know you think the same way. So all I'm really saying is that the statement "never buy a 1/2 point" should be amended to "never buy the first 1/2 point for 10 cents."
Buying a 1/2 point, by shopping at other books, can sometimes be profitable. And buying, I think it the 5th half-point, for 10 cents, is profitable. Meaning, if you can choose between -7 -110 and -9 -140 and-9.5 -150, that 1/2 point from -9 to -9.5 for 10 more cents might be profitable. (above numbers for illustration purposes only).
For example, if I can get +7 -105 at 5Dimes, or +7.5 -111 at another book, which is better? That, to me, is where Ganchrow's calculator comes in handy.
From your own followup post, I know you think the same way. So all I'm really saying is that the statement "never buy a 1/2 point" should be amended to "never buy the first 1/2 point for 10 cents."
Buying a 1/2 point, by shopping at other books, can sometimes be profitable. And buying, I think it the 5th half-point, for 10 cents, is profitable. Meaning, if you can choose between -7 -110 and -9 -140 and-9.5 -150, that 1/2 point from -9 to -9.5 for 10 more cents might be profitable. (above numbers for illustration purposes only).