What does "radical leaps" mean in this context?
Many sayings contain germs of truth, and some are indeed profound, but they aren't reliable sources of knowledge and can be misleading. For example, take the saying 'You can't teach an old dog new tricks'. This isn't true of all dogs, and certainly isn't true of all human beings: there are many older people who are capable of making radical leaps in their ability.

What does "radical leaps" mean in this context?

Thanks!

Question

What does "radical leaps" mean in this context?
Many sayings contain germs of truth, and some are indeed profound, but they aren't reliable sources of knowledge and can be misleading. For example, take the saying 'You can't teach an old dog new tricks'. This isn't true of all dogs, and certainly isn't true of all human beings: there are many older people who are capable of making radical leaps in their ability.

What does "radical leaps" mean in this context?

Thanks!

Answer

This is another example of bad English.

A leap is a forceful jump.  Normally ones says a big, huge, great, phenomenal leap.  Radical is not the correct adjective.

Radical means "characterised by a significant departure from tradition; relating to or affecting the fundamental nature", as in a radical change, a radical overhaul, radical reforms, a radical proposal.

"a radical leap in ability" is definitely bad English.  Don't use it.

Answer

Radical in this context just means very significant or large.   So it's saying that some old people could still make a huge amount of progress in their skills or abilities, despite their age.