Practice vs Meet-Times, etc

Any good resources or rules-of-thumb to predict race/meet times from training? Do you just use time trials, can you use your 100 base-times, descend sets or pace work? I'm curious as to where I am at early in this season and would like to compare/project that to a meet setting. I feel like once-upon-a-time I had a gestalt for judging practice performance that let me understand where my training was at. Alternatively, does my question even make sense? The ratio or difference for Meet times vs practice times varies from one swimmer to the next., swimmers can have different ratios for different strokes. I tend to swim pretty fast in practice and a bit faster in meets. Some swimmers swim way faster in meets Than they do in practice, I've also seen swimmers swim faster in practice than in meets.

Any good resources or rules-of-thumb to predict race/meet times from training? Do you just use time trials, can you use your 100 base-times, descend sets or pace work? I'm curious as to where I am at early in this season and would like to compare/project that to a meet setting. I feel like once-upon-a-time I had a gestalt for judging practice performance that let me understand where my training was at. Alternatively, does my question even make sense? The ratio or difference for Meet times vs practice times varies from one swimmer to the next., swimmers can have different ratios for different strokes. I tend to swim pretty fast in practice and a bit faster in meets. Some swimmers swim way faster in meets Than they do in practice, I've also seen swimmers swim faster in practice than in meets.