DOC: adding reference for sync vs async queries

Author: bsipocz

tutorials/cosmodc2/cosmoDC2_TAP_access.md

@@ -79,7 +79,9 @@ result = service.run_async(adql)
 result
 ```
 
-The above query shows that there are 597,488,849 redshifts in this table.
+The above query shows that there are 597,488,849 redshifts in this table. 
+Running ``count`` on an entire table is an expensive operation, therefore we ran it asynchronously to avoid any potential timeout issues. 
+To learn more about synchronous versus asynchronous PyVO queries please read the [relevant PyVO documentation](https://pyvo.readthedocs.io/en/latest/dal/index.html#synchronous-vs-asynchronous-query).
 
 +++
 
@@ -125,7 +127,7 @@ adql
 Now we can use the previously-defined service to execute the query with the spatial contraint.
 
 ```{code-cell} ipython3
-cone_results = service.run_async(adql)
+cone_results = service.run_sync(adql)
 ```
 
 ```{code-cell} ipython3
@@ -151,7 +153,7 @@ We can easily see form this plot that the simulated galaxies go out to z = 3.
 
 Now let's visualize the galaxy main sequence at z = 2.0. First, we'll do a narrow redshift cut with no spatial constraint.
 
-Let's do it as an asynchronous search since this might take awhile.
+Let's do it as an asynchronous search since this might take awhile, too.
 
 ```{code-cell} ipython3
 service = vo.dal.TAPService("https://irsa.ipac.caltech.edu/TAP")
@@ -188,4 +190,4 @@ plt.show()
 
 **Updated:** 2024-07-24
 
-**Contact:** [the IRSA Helpdesk](https://irsa.ipac.caltech.edu/docs/help_desk.html) with questions or reporting problems.
+**Contact:** [the IRSA Helpdesk](https://irsa.ipac.caltech.edu/docs/help_desk.html) with questions or reporting problems.