1. It makes sense on your point of view that it would get penalty for researching late tech too early
2. This isn't the case, despite of this as I said earlier from #1, it would give a lot of bonuses on those guns and radar tech in terms of detection and range, giving you an advantage over your enemies. However, getting radar tech and other late techs on Pre-Dreadnought era ships (mostly for battleships and cruisers) is entertaining to watch that is a entertainment purposes only