Common table expression - parsing questions

Couple of questions:

1. Why does Postgres not throw a parsing error during sqlPrepare for this
statement vs at sqlExecute

with t_cte ( c1, ctr ) as (
select 1,0 from tversion union
select 2,0 from tversion union all
select c1, ctr + 1 from t_cte where c1=1 and ctr < 5 union all
select c1, ctr + 1 from t_cte where c1=2 and ctr < 5)
select c1, ctr from t_cte

2. Do you intend to remove the requirement to include the recursive keyword
- as other vendors allow

3. Is it a documented restriction that you can only have one reference to
the CTE .. see above example which fails while this modified version works.
The former
works in other vendors.

with recursive t_cte ( c1, ctr ) as (
select 1,0 from tversion union
select 2,0 from tversion union all
select c1, ctr + 1 from t_cte where c1=1 and ctr < 5 )
select c1, ctr from t_cte