I run O27 now but for many years used O and these switches. I NEVER had to slow down rolling thru them and NEVER had to consider their relative location to other switches. I NEVER made any accommodations for them.
I had 14 PW pieces of rolling stock and never had problems with any of them going thru the switches. Maybe the weight suggestion has some merit because all of my PW cars were certainly not light.
I only say that because some of the suggestions, while good, sure don't match to my experiences. I used them for the better part of 25 years.
You mentioned the 'indent' on the rail where the swivel fits into. When I first went to O27 I used Liionel switches and had that same problem with a few of them. I don't recall how I resolved it but I do know that I kept playing with it and did eventually. I wish I could remember so as to help you out.
Good luck and I know you'll solve this.
- walt
