@Override
    public boolean isParallel() {
        return false;
    }
Always returns false. Seq streams are always sequential and, as such,
doesn't support parallelization.

@return false
@see <a href="https://github.com/jOOQ/jOOL/issues/130">jOOL Issue #130</a>
jOOL/src/main/java/org/jooq/lambda/SeqImpl.java