Large Transport
Flight Crew Air Transport Pilot (ATP)
Confusion; Workload
ATC Issue All Types; Deviation / Discrepancy - Procedural Published Material / Policy
General None Reported / Taken
Human Factors; Procedure
VANZE 1 Arrival.  Set up for 27 because winds 250 at 16. 18L/R; 27 in use. Taken off arrival immediately with vector and slow to 290 knots. Descend to FL240. Cleared to VANZE descend Via except maintain speed. Shortly given Another Vector and slow to 280 knots; then 250 knots; then 210 knots. Descend to 7;000 given very early on vector and expect RNAV to 18L in Box to change. Then given another vector (aligning with last leg of VANZE arrival). Then cleared descend via VANZE 1< maintain speed 190. Working in FMS and noted Pilot Flying (PF) put in 3;000 ft which is what I expected. Then realized we were still short of MEBEE (cross above 8;000 feet). Not cleared to MEBEE. Decided to have Pilot Flying (PF) stay at 7;000 feet until crossing since aligned with; and ask for better clearance; but given frequency change. Next controller cleared us to 3;000 feet alleviating concern. Noticed he was giving ILS (LOC clearances). Put in FMS. cleared for visual in the end to 18L.Need more planning ahead on ATC part. Not necessary to give all of the changes and keep on an RNAV. One or the other would be preferred. Too much time spent in FMS on a relatively clear day.  More accurate direction given earlier would be appreciated.Less mixing of procedures would help. RNAV and Training fine and Understood. So many changes vectors; airspeeds; altitudes given should revert to manual arrival with final vector and altitude with airspeed. Cannot pass off arriving aircraft as safely by putting back on an arrival after changing everything without very explicit clearance.
Captain laments the current ATC philosophy of using RNAV arrivals then making changes to the airspeed and altitude restrictions; then vectoring off and back on the arrival without a clear altitude assignment.