Flats and Compliance

[Owen]

I have a very, very old set of Chromes on a P bass. They are perfection. 

 

I fancied the 5 string experience. So I put a set on a 33" bass I have. This has a bar behind the nut as an all purpose string retainer thang. It was horrible. They were tight and super unforgiving. Was this because of the vicious break angle behind the nut? This does not feel like an issue with the round core nickels I have on the bass usually. 

[Misdee]

Those Chromes are pretty stiff flats in the scheme of things. Looking at the problems from the reverse angle, is there anything exceptional about the P Bass that makes them so playable on that bass? A non-angled headstock, yes, but I would still expect Chromes to be pretty tense on a typical Fender.