In my opinion if you can make this set then you should be able to hold a much faster pace than 1:30 on a 1500. When I do pace sets I aim for a 2:1 swim to rest ratio and I find that's pretty difficult. So for a 1:30 pace that would mean a 2:15 sendoff. There's no way I could hold my pace with only five seconds rest.
Knowing what I know about Tim and knowing his goal is 22:30, the 1:30s on 1:35 will work for him. He will end up going faster than 22:30 and he will negatively split the race. He has no experience with the 1500 and a little experience with the 800, so going out with a comfortable pace and having plenty to come home strong I think is a good strategy for a first 1500. I used that strategy for my first 1500 last summer and am planning on swimming the event again.
If it wasn't his first 1500, and it wasn't Tim, I wouldn't give any advice on a 1500. It is certainly not a race I know anything about and my suggestions can't be generalized.
In my opinion if you can make this set then you should be able to hold a much faster pace than 1:30 on a 1500. When I do pace sets I aim for a 2:1 swim to rest ratio and I find that's pretty difficult. So for a 1:30 pace that would mean a 2:15 sendoff. There's no way I could hold my pace with only five seconds rest.
Knowing what I know about Tim and knowing his goal is 22:30, the 1:30s on 1:35 will work for him. He will end up going faster than 22:30 and he will negatively split the race. He has no experience with the 1500 and a little experience with the 800, so going out with a comfortable pace and having plenty to come home strong I think is a good strategy for a first 1500. I used that strategy for my first 1500 last summer and am planning on swimming the event again.
If it wasn't his first 1500, and it wasn't Tim, I wouldn't give any advice on a 1500. It is certainly not a race I know anything about and my suggestions can't be generalized.