diff --git a/CHANGELOG.md b/CHANGELOG.md
index e18bea53..fcc12873 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -3,7 +3,7 @@
 ## Version 6.0.0
 * Update Makevars for ARM version of Windows.
 * Sanitize internal usage of `do.call` to avoid huge backtraces.
-* Support lower triangular `distmat` objects for symmetric distances (#77).
+* Support lower triangular `distmat` objects for symmetric distances (#77) - breaking change.
 
 ## Version 5.5.12
 * Remove explicit C++ requirements.
diff --git a/R/DISTANCES-sdtw.R b/R/DISTANCES-sdtw.R
index 7c3c9a72..f990d0bd 100644
--- a/R/DISTANCES-sdtw.R
+++ b/R/DISTANCES-sdtw.R
@@ -21,6 +21,12 @@
 #'
 #' `r roxygen_proxy_symmetric()`
 #'
+#' Note that, due to the fact that this distance is not always zero when a series is compared
+#' against itself, this optimization is likely problematic for soft-DTW, as the `dist` object will
+#' be handled by many functions as if it had only zeroes in the diagonal. An exception is
+#' [tsclust()] when using partitional clustering with PAM centroids---actual diagonal values will
+#' be calculated and considered internally in that case.
+#'
 #' @references
 #'
 #' Cuturi, M., & Blondel, M. (2017). Soft-DTW: a Differentiable Loss Function for Time-Series. arXiv
diff --git a/R/RD-helpers.R b/R/RD-helpers.R
index 31262a4a..d074652f 100644
--- a/R/RD-helpers.R
+++ b/R/RD-helpers.R
@@ -26,6 +26,9 @@ See the parallelization vignette for more information - `browseVignettes(\"dtwcl
 
 roxygen_proxy_symmetric <- function() {
     "It also includes symmetric optimizations to calculate only half a distance matrix when appropriate---only one list of series should be provided in `x`.
+Starting with version 6.0.0, this optimization means that the function returns an array with the lower triangular values of the distance matrix,
+similar to what [stats::dist()] does;
+see [DistmatLowerTriangular-class] for a helper to access elements as it if were a normal matrix.
 If you want to avoid this optimization, call [proxy::dist] by giving the same list of series in both `x` and `y`."
 }
 
diff --git a/inst/NEWS.Rd b/inst/NEWS.Rd
index 3156ff5e..5293f7a1 100644
--- a/inst/NEWS.Rd
+++ b/inst/NEWS.Rd
@@ -11,6 +11,6 @@
 \itemize{
     \item Update Makevars for ARM version of Windows.
     \item Sanitize internal usage of \code{do.call} to avoid huge backtraces.
-    \item Support lower triangular \code{distmat} objects for symmetric distances. See PR #77 on GitHub.
+    \item Support lower triangular \code{distmat} objects for symmetric distances. This is a slightly breaking change, see PR #77 on GitHub.
 }
 }
diff --git a/man/GAK.Rd b/man/GAK.Rd
index 0dc1cb5f..73e75843 100644
--- a/man/GAK.Rd
+++ b/man/GAK.Rd
@@ -89,6 +89,9 @@ this function will default to 1 thread per worker.
 See the parallelization vignette for more information - \code{browseVignettes("dtwclust")}
 
 It also includes symmetric optimizations to calculate only half a distance matrix when appropriate---only one list of series should be provided in \code{x}.
+Starting with version 6.0.0, this optimization means that the function returns an array with the lower triangular values of the distance matrix,
+similar to what \code{\link[stats:dist]{stats::dist()}} does;
+see \linkS4class{DistmatLowerTriangular} for a helper to access elements as it if were a normal matrix.
 If you want to avoid this optimization, call \link[proxy:dist]{proxy::dist} by giving the same list of series in both \code{x} and \code{y}.
 }
 
diff --git a/man/SBD.Rd b/man/SBD.Rd
index 7d070e23..c9af3bcc 100644
--- a/man/SBD.Rd
+++ b/man/SBD.Rd
@@ -63,6 +63,9 @@ this function will default to 1 thread per worker.
 See the parallelization vignette for more information - \code{browseVignettes("dtwclust")}
 
 It also includes symmetric optimizations to calculate only half a distance matrix when appropriate---only one list of series should be provided in \code{x}.
+Starting with version 6.0.0, this optimization means that the function returns an array with the lower triangular values of the distance matrix,
+similar to what \code{\link[stats:dist]{stats::dist()}} does;
+see \linkS4class{DistmatLowerTriangular} for a helper to access elements as it if were a normal matrix.
 If you want to avoid this optimization, call \link[proxy:dist]{proxy::dist} by giving the same list of series in both \code{x} and \code{y}.
 
 In some situations, e.g. for relatively small distance matrices, the overhead introduced by the
diff --git a/man/dtw_basic.Rd b/man/dtw_basic.Rd
index 0931f181..153a3329 100644
--- a/man/dtw_basic.Rd
+++ b/man/dtw_basic.Rd
@@ -88,6 +88,9 @@ this function will default to 1 thread per worker.
 See the parallelization vignette for more information - \code{browseVignettes("dtwclust")}
 
 It also includes symmetric optimizations to calculate only half a distance matrix when appropriate---only one list of series should be provided in \code{x}.
+Starting with version 6.0.0, this optimization means that the function returns an array with the lower triangular values of the distance matrix,
+similar to what \code{\link[stats:dist]{stats::dist()}} does;
+see \linkS4class{DistmatLowerTriangular} for a helper to access elements as it if were a normal matrix.
 If you want to avoid this optimization, call \link[proxy:dist]{proxy::dist} by giving the same list of series in both \code{x} and \code{y}.
 
 In order for symmetry to apply here, the following must be true: no window constraint is used
diff --git a/man/sdtw.Rd b/man/sdtw.Rd
index c829cf77..217356e1 100644
--- a/man/sdtw.Rd
+++ b/man/sdtw.Rd
@@ -41,7 +41,16 @@ this function will default to 1 thread per worker.
 See the parallelization vignette for more information - \code{browseVignettes("dtwclust")}
 
 It also includes symmetric optimizations to calculate only half a distance matrix when appropriate---only one list of series should be provided in \code{x}.
+Starting with version 6.0.0, this optimization means that the function returns an array with the lower triangular values of the distance matrix,
+similar to what \code{\link[stats:dist]{stats::dist()}} does;
+see \linkS4class{DistmatLowerTriangular} for a helper to access elements as it if were a normal matrix.
 If you want to avoid this optimization, call \link[proxy:dist]{proxy::dist} by giving the same list of series in both \code{x} and \code{y}.
+
+Note that, due to the fact that this distance is not always zero when a series is compared
+against itself, this optimization is likely problematic for soft-DTW, as the \code{dist} object will
+be handled by many functions as if it had only zeroes in the diagonal. An exception is
+\code{\link[=tsclust]{tsclust()}} when using partitional clustering with PAM centroids---actual diagonal values will
+be calculated and considered internally in that case.
 }
 
 \references{