I guess you're using 'hammering' in a very specific way, then. I use it any effort that feels pretty dang hard. I think you're using it more like an all out final sprint - I'd rather call those sprints as opposed to hammering, since you can definitely hammer for an hour, whereas you can't sprint for an hour.

Either way, you gotta ride hard and feel the hurt to get better. Even the pros acknowledge that cycling is largely about taking the suffering on the bike, both in practice, and then in the races.

You can do all the technique drills you want in cycling, but you're not going to get any faster unless you work harder, and usually a lot harder.

On the bike, you can hammer at any level - it's just relative. This guy might only be able to hammer a few miles of a measly 10 mile ride, but it'll yield more benefit than riding easy for those 10 miles.