comparision + parallelism

a)Ram writes better essays than I. incorrect
b)Ram writes better essays than I do. correct
c)Ram writes better than do I. incorrect

d)Ram is a better player than Shyam. incorrect
e)Ram is a better player than Shyam is. correct
f)Ram is a better player than is shyam. incorrect

Ram plays better than Shyam (Here Ram and Shyam are compared)
but in d) that's not the case

b)Ram writes better essays than I do. correct
d)Ram is a better player than Shyam. correct

Hi,
Would like to add something to Cans's post.
IMO Ram is a better player than Shyam.(Correct as well)

Ram writes better essays than I. I what "waiting for something"
Ram writes better essays than I do. correct,
Ram writes better than do I. Is it question?


Further,
Ram is a better player than Shyam. Sachin is a better player than Chris Gayle, Sachin plays better than Chris Gayle, Is sachin a better player than McGrath?
Now, If I says Sachin plays better than Donald does? will that be correct.

Ram is a better player than Shyam is.
Ram is a better player than is shyam. incorrect

What I feel and obtained from above discussion is:

Ram writes better essay than I do //correct...i agree
(here the things written are compared, and so verb is necessary)

Ram is a better player than Shyam. //Correct ...I agree
Ram is a better player than Shyam. //still confused
(here the qualities are compared)

Further, I want to ask which of the following is correct

Ram plays better than Shyam
Ram plays better than Shyam does
Ram plays better than does Shyam
(here the qualities of verb are compared)

experts..ur help needed plzz...this is one of the most confusing parts of grammar.