They mean the same and it is really a matter of style more than substance. "More so" is more formal sounding that just saying "more than." The "so" refers back to an adverb or adjective so you can use it when you don't want to repeat the adj/abv, the 'so' stands in for it. You can also use the constructions "equally so" and "less so" in the same way.

1. In mathematics at school we used one character ">" 2. When you are comparing the two adjectives like "Yan is a good lawyer, but Andy is better" ... so the expression "more so than" compared "linking techniques" with "arbitrary techniques" and the last one require more practice. I hope it will be useful for you :)

It emphasizes that the arbitrary techniques bigger than the linking techniques

It's actually not good English as written. Require even more practice 更需要的