9.5 on Windows seems terribly unable to deal with fields full of text?

[Geoff Canyon]

The ide seems slow in general, but put the contents of a 1 mb 80k line file, and the message box disables the IDE, with multi-second delays. Examine that value as a variable, and similarly but to a lesser extent things slow down. I remember having no trouble doing things like this in 8, maybe even 9 on my 6-year-old MacBook, which is in the shop getting a new battery. 

Anyone else? Any suggestions?