Yep. It has been mentioned by a few people in the know that a lot of the jap brand name valve springs do not have sufficient seat pressures when they are fitted without setting them up for intended use.
For example, a high boost/ high lift setup would need a modified seat pressure to suit, by either a correctly shimmed spring, setup to avoid coil bind.
Or a dual valve spring such as BC (brian crower) etc.
Due to Paul's fairly non standard setup, seat pressures could definately be an issue, as opposed to most people on here running bigger duration but not much lift and mild boost....
Or I could be just adding my 2cents lol...